Search Results

Search found 935 results on 38 pages for 'west wind'.

Page 6/38 | < Previous Page | 2 3 4 5 6 7 8 9 10 11 12 13  | Next Page >

  • Dynamically loading Assemblies to reduce Runtime Dependencies

    - by Rick Strahl
    I've been working on a request to the West Wind Application Configuration library to add JSON support. The config library is a very easy to use code-first approach to configuration: You create a class that holds the configuration data that inherits from a base configuration class, and then assign a persistence provider at runtime that determines where and how the configuration data is store. Currently the library supports .NET Configuration stores (web.config/app.config), XML files, SQL records and string storage.About once a week somebody asks me about JSON support and I've deflected this question for the longest time because frankly I think that JSON as a configuration store doesn't really buy a heck of a lot over XML. Both formats require the user to perform some fixup of the plain configuration data - in XML into XML tags, with JSON using JSON delimiters for properties and property formatting rules. Sure JSON is a little less verbose and maybe a little easier to read if you have hierarchical data, but overall the differences are pretty minor in my opinion. And yet - the requests keep rolling in.Hard Link Issues in a Component LibraryAnother reason I've been hesitant is that I really didn't want to pull in a dependency on an external JSON library - in this case JSON.NET - into the core library. If you're not using JSON.NET elsewhere I don't want a user to have to require a hard dependency on JSON.NET unless they want to use the JSON feature. JSON.NET is also sensitive to versions and doesn't play nice with multiple versions when hard linked. For example, when you have a reference to V4.4 in your project but the host application has a reference to version 4.5 you can run into assembly load problems. NuGet's Update-Package can solve some of this *if* you can recompile, but that's not ideal for a component that's supposed to be just plug and play. This is no criticism of JSON.NET - this really applies to any dependency that might change.  So hard linking the DLL can be problematic for a number reasons, but the primary reason is to not force loading of JSON.NET unless you actually need it when you use the JSON configuration features of the library.Enter Dynamic LoadingSo rather than adding an assembly reference to the project, I decided that it would be better to dynamically load the DLL at runtime and then use dynamic typing to access various classes. This allows me to run without a hard assembly reference and allows more flexibility with version number differences now and in the future.But there are also a couple of downsides:No assembly reference means only dynamic access - no compiler type checking or IntellisenseRequirement for the host application to have reference to JSON.NET or else get runtime errorsThe former is minor, but the latter can be problematic. Runtime errors are always painful, but in this case I'm willing to live with this. If you want to use JSON configuration settings JSON.NET needs to be loaded in the project. If this is a Web project, it'll likely be there already.So there are a few things that are needed to make this work:Dynamically create an instance and optionally attempt to load an Assembly (if not loaded)Load types into dynamic variablesUse Reflection for a few tasks like statics/enumsThe dynamic keyword in C# makes the formerly most difficult Reflection part - method calls and property assignments - fairly painless. But as cool as dynamic is it doesn't handle all aspects of Reflection. Specifically it doesn't deal with object activation, truly dynamic (string based) member activation or accessing of non instance members, so there's still a little bit of work left to do with Reflection.Dynamic Object InstantiationThe first step in getting the process rolling is to instantiate the type you need to work with. This might be a two step process - loading the instance from a string value, since we don't have a hard type reference and potentially having to load the assembly. Although the host project might have a reference to JSON.NET, that instance might have not been loaded yet since it hasn't been accessed yet. In ASP.NET this won't be a problem, since ASP.NET preloads all referenced assemblies on AppDomain startup, but in other executable project, assemblies are just in time loaded only when they are accessed.Instantiating a type is a two step process: Finding the type reference and then activating it. Here's the generic code out of my ReflectionUtils library I use for this:/// <summary> /// Creates an instance of a type based on a string. Assumes that the type's /// </summary> /// <param name="typeName">Common name of the type</param> /// <param name="args">Any constructor parameters</param> /// <returns></returns> public static object CreateInstanceFromString(string typeName, params object[] args) { object instance = null; Type type = null; try { type = GetTypeFromName(typeName); if (type == null) return null; instance = Activator.CreateInstance(type, args); } catch { return null; } return instance; } /// <summary> /// Helper routine that looks up a type name and tries to retrieve the /// full type reference in the actively executing assemblies. /// </summary> /// <param name="typeName"></param> /// <returns></returns> public static Type GetTypeFromName(string typeName) { Type type = null; // Let default name binding find it type = Type.GetType(typeName, false); if (type != null) return type; // look through assembly list var assemblies = AppDomain.CurrentDomain.GetAssemblies(); // try to find manually foreach (Assembly asm in assemblies) { type = asm.GetType(typeName, false); if (type != null) break; } return type; } To use this for loading JSON.NET I have a small factory function that instantiates JSON.NET and sets a bunch of configuration settings on the generated object. The startup code also looks for failure and tries loading up the assembly when it fails since that's the main reason the load would fail. Finally it also caches the loaded instance for reuse (according to James the JSON.NET instance is thread safe and quite a bit faster when cached). Here's what the factory function looks like in JsonSerializationUtils:/// <summary> /// Dynamically creates an instance of JSON.NET /// </summary> /// <param name="throwExceptions">If true throws exceptions otherwise returns null</param> /// <returns>Dynamic JsonSerializer instance</returns> public static dynamic CreateJsonNet(bool throwExceptions = true) { if (JsonNet != null) return JsonNet; lock (SyncLock) { if (JsonNet != null) return JsonNet; // Try to create instance dynamic json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); if (json == null) { try { var ass = AppDomain.CurrentDomain.Load("Newtonsoft.Json"); json = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.JsonSerializer"); } catch (Exception ex) { if (throwExceptions) throw; return null; } } if (json == null) return null; json.ReferenceLoopHandling = (dynamic) ReflectionUtils.GetStaticProperty("Newtonsoft.Json.ReferenceLoopHandling", "Ignore"); // Enums as strings in JSON dynamic enumConverter = ReflectionUtils.CreateInstanceFromString("Newtonsoft.Json.Converters.StringEnumConverter"); json.Converters.Add(enumConverter); JsonNet = json; } return JsonNet; }This code's purpose is to return a fully configured JsonSerializer instance. As you can see the code tries to create an instance and when it fails tries to load the assembly, and then re-tries loading.Once the instance is loaded some configuration occurs on it. Specifically I set the ReferenceLoopHandling option to not blow up immediately when circular references are encountered. There are a host of other small config setting that might be useful to set, but the default seem to be good enough in recent versions. Note that I'm setting ReferenceLoopHandling which requires an Enum value to be set. There's no real easy way (short of using the cardinal numeric value) to set a property or pass parameters from static values or enums. This means I still need to use Reflection to make this work. I'm using the same ReflectionUtils class I previously used to handle this for me. The function looks up the type and then uses Type.InvokeMember() to read the static property.Another feature I need is have Enum values serialized as strings rather than numeric values which is the default. To do this I can use the StringEnumConverter to convert enums to strings by adding it to the Converters collection.As you can see there's still a bit of Reflection to be done even in C# 4+ with dynamic, but with a few helpers this process is relatively painless.Doing the actual JSON ConversionFinally I need to actually do my JSON conversions. For the Utility class I need serialization that works for both strings and files so I created four methods that handle these tasks two each for serialization and deserialization for string and file.Here's what the File Serialization looks like:/// <summary> /// Serializes an object instance to a JSON file. /// </summary> /// <param name="value">the value to serialize</param> /// <param name="fileName">Full path to the file to write out with JSON.</param> /// <param name="throwExceptions">Determines whether exceptions are thrown or false is returned</param> /// <param name="formatJsonOutput">if true pretty-formats the JSON with line breaks</param> /// <returns>true or false</returns> public static bool SerializeToFile(object value, string fileName, bool throwExceptions = false, bool formatJsonOutput = false) { dynamic writer = null; FileStream fs = null; try { Type type = value.GetType(); var json = CreateJsonNet(throwExceptions); if (json == null) return false; fs = new FileStream(fileName, FileMode.Create); var sw = new StreamWriter(fs, Encoding.UTF8); writer = Activator.CreateInstance(JsonTextWriterType, sw); if (formatJsonOutput) writer.Formatting = (dynamic)Enum.Parse(FormattingType, "Indented"); writer.QuoteChar = '"'; json.Serialize(writer, value); } catch (Exception ex) { Debug.WriteLine("JsonSerializer Serialize error: " + ex.Message); if (throwExceptions) throw; return false; } finally { if (writer != null) writer.Close(); if (fs != null) fs.Close(); } return true; }You can see more of the dynamic invocation in this code. First I grab the dynamic JsonSerializer instance using the CreateJsonNet() method shown earlier which returns a dynamic. I then create a JsonTextWriter and configure a couple of enum settings on it, and then call Serialize() on the serializer instance with the JsonTextWriter that writes the output to disk. Although this code is dynamic it's still fairly short and readable.For full circle operation here's the DeserializeFromFile() version:/// <summary> /// Deserializes an object from file and returns a reference. /// </summary> /// <param name="fileName">name of the file to serialize to</param> /// <param name="objectType">The Type of the object. Use typeof(yourobject class)</param> /// <param name="binarySerialization">determines whether we use Xml or Binary serialization</param> /// <param name="throwExceptions">determines whether failure will throw rather than return null on failure</param> /// <returns>Instance of the deserialized object or null. Must be cast to your object type</returns> public static object DeserializeFromFile(string fileName, Type objectType, bool throwExceptions = false) { dynamic json = CreateJsonNet(throwExceptions); if (json == null) return null; object result = null; dynamic reader = null; FileStream fs = null; try { fs = new FileStream(fileName, FileMode.Open, FileAccess.Read); var sr = new StreamReader(fs, Encoding.UTF8); reader = Activator.CreateInstance(JsonTextReaderType, sr); result = json.Deserialize(reader, objectType); reader.Close(); } catch (Exception ex) { Debug.WriteLine("JsonNetSerialization Deserialization Error: " + ex.Message); if (throwExceptions) throw; return null; } finally { if (reader != null) reader.Close(); if (fs != null) fs.Close(); } return result; }This code is a little more compact since there are no prettifying options to set. Here JsonTextReader is created dynamically and it receives the output from the Deserialize() operation on the serializer.You can take a look at the full JsonSerializationUtils.cs file on GitHub to see the rest of the operations, but the string operations are very similar - the code is fairly repetitive.These generic serialization utilities isolate the dynamic serialization logic that has to deal with the dynamic nature of JSON.NET, and any code that uses these functions is none the wiser that JSON.NET is dynamically loaded.Using the JsonSerializationUtils WrapperThe final consumer of the SerializationUtils wrapper is an actual ConfigurationProvider, that is responsible for handling reading and writing JSON values to and from files. The provider is simple a small wrapper around the SerializationUtils component and there's very little code to make this work now:The whole provider looks like this:/// <summary> /// Reads and Writes configuration settings in .NET config files and /// sections. Allows reading and writing to default or external files /// and specification of the configuration section that settings are /// applied to. /// </summary> public class JsonFileConfigurationProvider<TAppConfiguration> : ConfigurationProviderBase<TAppConfiguration> where TAppConfiguration: AppConfiguration, new() { /// <summary> /// Optional - the Configuration file where configuration settings are /// stored in. If not specified uses the default Configuration Manager /// and its default store. /// </summary> public string JsonConfigurationFile { get { return _JsonConfigurationFile; } set { _JsonConfigurationFile = value; } } private string _JsonConfigurationFile = string.Empty; public override bool Read(AppConfiguration config) { var newConfig = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfiguration)) as TAppConfiguration; if (newConfig == null) { if(Write(config)) return true; return false; } DecryptFields(newConfig); DataUtils.CopyObjectData(newConfig, config, "Provider,ErrorMessage"); return true; } /// <summary> /// Return /// </summary> /// <typeparam name="TAppConfig"></typeparam> /// <returns></returns> public override TAppConfig Read<TAppConfig>() { var result = JsonSerializationUtils.DeserializeFromFile(JsonConfigurationFile, typeof(TAppConfig)) as TAppConfig; if (result != null) DecryptFields(result); return result; } /// <summary> /// Write configuration to XmlConfigurationFile location /// </summary> /// <param name="config"></param> /// <returns></returns> public override bool Write(AppConfiguration config) { EncryptFields(config); bool result = JsonSerializationUtils.SerializeToFile(config, JsonConfigurationFile,false,true); // Have to decrypt again to make sure the properties are readable afterwards DecryptFields(config); return result; } }This incidentally demonstrates how easy it is to create a new provider for the West Wind Application Configuration component. Simply implementing 3 methods will do in most cases.Note this code doesn't have any dynamic dependencies - all that's abstracted away in the JsonSerializationUtils(). From here on, serializing JSON is just a matter of calling the static methods on the SerializationUtils class.Already, there are several other places in some other tools where I use JSON serialization this is coming in very handy. With a couple of lines of code I was able to add JSON.NET support to an older AJAX library that I use replacing quite a bit of code that was previously in use. And for any other manual JSON operations (in a couple of apps I use JSON Serialization for 'blob' like document storage) this is also going to be handy.Performance?Some of you might be thinking that using dynamic and Reflection can't be good for performance. And you'd be right… In performing some informal testing it looks like the performance of the native code is nearly twice as fast as the dynamic code. Most of the slowness is attributable to type lookups. To test I created a native class that uses an actual reference to JSON.NET and performance was consistently around 85-90% faster with the referenced code. This will change though depending on the size of objects serialized - the larger the object the more processing time is spent inside the actual dynamically activated components and the less difference there will be. Dynamic code is always slower, but how much it really affects your application primarily depends on how frequently the dynamic code is called in relation to the non-dynamic code executing. In most situations where dynamic code is used 'to get the process rolling' as I do here the overhead is small enough to not matter.All that being said though - I serialized 10,000 objects in 80ms vs. 45ms so this is hardly slouchy performance. For the configuration component speed is not that important because both read and write operations typically happen once on first access and then every once in a while. But for other operations - say a serializer trying to handle AJAX requests on a Web Server one would be well served to create a hard dependency.Dynamic Loading - Worth it?Dynamic loading is not something you need to worry about but on occasion dynamic loading makes sense. But there's a price to be paid in added code  and a performance hit which depends on how frequently the dynamic code is accessed. But for some operations that are not pivotal to a component or application and are only used under certain circumstances dynamic loading can be beneficial to avoid having to ship extra files adding dependencies and loading down distributions. These days when you create new projects in Visual Studio with 30 assemblies before you even add your own code, trying to keep file counts under control seems like a good idea. It's not the kind of thing you do on a regular basis, but when needed it can be a useful option in your toolset… © Rick Strahl, West Wind Technologies, 2005-2013Posted in .NET  C#   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • GridBagConstraints problem-moved to left and size isn't the same

    - by Damir
    I have in Java two panels which need to have same layout, there is my functions for initializations panels. private void InitializePanelCom(){ pnlCom=new JPanel(); pnlCom.setSize(300,160); pnlCom.setLocation(10, 60); add(pnlCom); GridBagLayout gb=new GridBagLayout(); GridBagConstraints gc=new GridBagConstraints(); pnlCom.setLayout(gb); jLabelcommPort = setJLabel("Com Port : "); jLabelbaudRate = setJLabel("Baud Rate : "); jLabelplcAddress = setJLabel("Plc Address : "); jLabelsendTime = setJLabel("Send Time : "); jLabelx50 = setJLabel(" x 50 ms (2 - 99)"); jComboBoxcommPort = setJComboBox(commPortList); jComboBoxbaudRate = setJComboBox(bitRateList); jTextAreaPlcAddress = setJTextField(""); jTextAreaSendTime = setJTextField(""); gc.insets = new Insets(10,0,0,0); gc.ipadx = 120; gc.weightx = 1; gc.gridx = 0; gc.gridy = 0; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jLabelcommPort,gc); gc.insets = new Insets(10,0,0,0); gc.ipadx = 120; gc.weightx = 1; gc.gridx = 1; gc.gridy = 0; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jComboBoxcommPort,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=0; gc.gridy=1; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jLabelbaudRate,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=1; gc.gridy=1; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jComboBoxbaudRate,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=0; gc.gridy=2; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jLabelplcAddress,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=1; gc.gridy=2; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jTextAreaPlcAddress,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=0; gc.gridy=3; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jLabelsendTime,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=1; gc.gridy=3; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jTextAreaSendTime,gc); gc.insets=new Insets(10,0,0,0); gc.ipadx=120; gc.weightx=1; gc.gridx=2; gc.gridy=3; gc.anchor=GridBagConstraints.EAST; pnlCom.add(jLabelx50,gc); } ![alt text][1] private void InitializePanelTcp(){ pnlTcp=new JPanel(); pnlTcp.setSize(300,160); pnlTcp.setLocation(10, 60); add(pnlTcp); GridBagLayout gb=new GridBagLayout(); GridBagConstraints gc=new GridBagConstraints(); pnlTcp.setLayout(gb); lblIPAddress=setJLabel("IP Address : "); txtIPAddress=setJTextField(""); lblPort=setJLabel("Port : "); txtPort=setJTextField(""); cmbBaudRateTCP = setJComboBox(bitRateList); lblBaudRateTCP = setJLabel("Baud Rate : "); lblParityCheck=setJLabel("Parity check : "); txtParityCheck=setJTextField(""); gc.insets = new Insets(10,0,0,0); //gc.ipadx = 20; gc.weightx = 0.3; gc.gridx = 0; gc.gridy = 0; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(lblIPAddress,gc); gc.insets = new Insets(10,0,0,0); //gc.ipadx = 80; gc.weightx = 0.7; gc.gridx = 1; gc.gridy = 0; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(txtIPAddress,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=120; gc.weightx=0.3; gc.gridx=0; gc.gridy=1; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(lblPort,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=80; gc.weightx=0.7; gc.gridx=1; gc.gridy=1; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(txtPort,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=120; gc.weightx=0.3; gc.gridx=0; gc.gridy=2; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(lblBaudRateTCP,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=0; gc.weightx=0.7; gc.gridx=1; gc.gridy=2; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(cmbBaudRateTCP,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=120; gc.weightx=0.3; gc.gridx=0; gc.gridy=3; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(lblParityCheck,gc); gc.insets=new Insets(10,0,0,0); //gc.ipadx=0; gc.weightx=1.7; gc.gridx=1; gc.gridy=3; gc.anchor=GridBagConstraints.WEST; pnlTcp.add(txtParityCheck,gc); } Problem is that second panel (initializetcp, second picture doesn't look the same, labels are moved at left , it is different ). Can anybody help, I am new with GridBagContsraints at all ?

    Read the article

  • How do I use XML prefixes in C#?

    - by Andrew Mock
    EDIT: I have now published my app: http://pastebin.com/PYAxaTHU I was trying to make console-based application that returns my temperature. using System; using System.Xml; namespace GetTemp { class Program { static void Main(string[] args) { XmlDocument doc = new XmlDocument(); doc.LoadXml(downloadWebPage( "http://www.andrewmock.com/uploads/example.xml" )); XmlNamespaceManager man = new XmlNamespaceManager(doc.NameTable); man.AddNamespace("aws", "www.aws.com/aws"); XmlNode weather = doc.SelectSingleNode("aws:weather", man); Console.WriteLine(weather.InnerText); Console.ReadKey(false); } } } Here is the sample XML: <aws:weather xmlns:aws="http://www.aws.com/aws"> <aws:api version="2.0"/> <aws:WebURL>http://weather.weatherbug.com/WA/Kenmore-weather.html?ZCode=Z5546&Units=0&stat=BOTHL</aws:WebURL> <aws:InputLocationURL>http://weather.weatherbug.com/WA/Kenmore-weather.html?ZCode=Z5546&Units=0</aws:InputLocationURL> <aws:station requestedID="BOTHL" id="BOTHL" name="Moorlands ES" city="Kenmore" state=" WA" zipcode="98028" country="USA" latitude="47.7383346557617" longitude="-122.230278015137"/> <aws:current-condition icon="http://deskwx.weatherbug.com/images/Forecast/icons/cond024.gif">Mostly Cloudy</aws:current-condition> <aws:temp units="&deg;F">40.2</aws:temp> <aws:rain-today units=""">0</aws:rain-today> <aws:wind-speed units="mph">0</aws:wind-speed> <aws:wind-direction>WNW</aws:wind-direction> <aws:gust-speed units="mph">5</aws:gust-speed> <aws:gust-direction>NW</aws:gust-direction> </aws:weather> I'm just not sure how to use XML prefixes correctly here. What is wrong with this?

    Read the article

  • A free standing ASP.NET Pager Web Control

    - by Rick Strahl
    Paging in ASP.NET has been relatively easy with stock controls supporting basic paging functionality. However, recently I built an MVC application and one of the things I ran into was that I HAD TO build manual paging support into a few of my pages. Dealing with list controls and rendering markup is easy enough, but doing paging is a little more involved. I ended up with a small but flexible component that can be dropped anywhere. As it turns out the task of creating a semi-generic Pager control for MVC was fairly easily. Now I’m back to working in Web Forms and thought to myself that the way I created the pager in MVC actually would also work in ASP.NET – in fact quite a bit easier since the whole thing can be conveniently wrapped up into an easily reusable control. A standalone pager would provider easier reuse in various pages and a more consistent pager display regardless of what kind of 'control’ the pager is associated with. Why a Pager Control? At first blush it might sound silly to create a new pager control – after all Web Forms has pretty decent paging support, doesn’t it? Well, sort of. Yes the GridView control has automatic paging built in and the ListView control has the related DataPager control. The built in ASP.NET paging has several issues though: Postback and JavaScript requirements If you look at paging links in ASP.NET they are always postback links with javascript:__doPostback() calls that go back to the server. While that works fine and actually has some benefit like the fact that paging saves changes to the page and post them back, it’s not very SEO friendly. Basically if you use javascript based navigation nosearch engine will follow the paging links which effectively cuts off list content on the first page. The DataPager control does support GET based links via the QueryStringParameter property, but the control is effectively tied to the ListView control (which is the only control that implements IPageableItemContainer). DataSource Controls required for Efficient Data Paging Retrieval The only way you can get paging to work efficiently where only the few records you display on the page are queried for and retrieved from the database you have to use a DataSource control - only the Linq and Entity DataSource controls  support this natively. While you can retrieve this data yourself manually, there’s no way to just assign the page number and render the pager based on this custom subset. Other than that default paging requires a full resultset for ASP.NET to filter the data and display only a subset which can be very resource intensive and wasteful if you’re dealing with largish resultsets (although I’m a firm believer in returning actually usable sets :-}). If you use your own business layer that doesn’t fit an ObjectDataSource you’re SOL. That’s a real shame too because with LINQ based querying it’s real easy to retrieve a subset of data that is just the data you want to display but the native Pager functionality doesn’t support just setting properties to display just the subset AFAIK. DataPager is not Free Standing The DataPager control is the closest thing to a decent Pager implementation that ASP.NET has, but alas it’s not a free standing component – it works off a related control and the only one that it effectively supports from the stock ASP.NET controls is the ListView control. This means you can’t use the same data pager formatting for a grid and a list view or vice versa and you’re always tied to the control. Paging Events In order to handle paging you have to deal with paging events. The events fire at specific time instances in the page pipeline and because of this you often have to handle data binding in a way to work around the paging events or else end up double binding your data sources based on paging. Yuk. Styling The GridView pager is a royal pain to beat into submission for styled rendering. The DataPager control has many more options and template layout and it renders somewhat cleaner, but it too is not exactly easy to get a decent display for. Not a Generic Solution The problem with the ASP.NET controls too is that it’s not generic. GridView, DataGrid use their own internal paging, ListView can use a DataPager and if you want to manually create data layout – well you’re on your own. IOW, depending on what you use you likely have very different looking Paging experiences. So, I figured I’ve struggled with this once too many and finally sat down and built a Pager control. The Pager Control My goal was to create a totally free standing control that has no dependencies on other controls and certainly no requirements for using DataSource controls. The idea is that you should be able to use this pager control without any sort of data requirements at all – you should just be able to set properties and be able to display a pager. The Pager control I ended up with has the following features: Completely free standing Pager control – no control or data dependencies Complete manual control – Pager can render without any data dependency Easy to use: Only need to set PageSize, ActivePage and TotalItems Supports optional filtering of IQueryable for efficient queries and Pager rendering Supports optional full set filtering of IEnumerable<T> and DataTable Page links are plain HTTP GET href Links Control automatically picks up Page links on the URL and assigns them (automatic page detection no page index changing events to hookup) Full CSS Styling support On the downside there’s no templating support for the control so the layout of the pager is relatively fixed. All elements however are stylable and there are options to control the text, and layout options such as whether to display first and last pages and the previous/next buttons and so on. To give you an idea what the pager looks like, here are two differently styled examples (all via CSS):   The markup for these two pagers looks like this: <ww:Pager runat="server" id="ItemPager" PageSize="5" PageLinkCssClass="gridpagerbutton" SelectedPageCssClass="gridpagerbutton-selected" PagesTextCssClass="gridpagertext" CssClass="gridpager" RenderContainerDiv="true" ContainerDivCssClass="gridpagercontainer" MaxPagesToDisplay="6" PagesText="Item Pages:" NextText="next" PreviousText="previous" /> <ww:Pager runat="server" id="ItemPager2" PageSize="5" RenderContainerDiv="true" MaxPagesToDisplay="6" /> The latter example uses default style settings so it there’s not much to set. The first example on the other hand explicitly assigns custom styles and overrides a few of the formatting options. Styling The styling is based on a number of CSS classes of which the the main pager, pagerbutton and pagerbutton-selected classes are the important ones. Other styles like pagerbutton-next/prev/first/last are based on the pagerbutton style. The default styling shown for the red outlined pager looks like this: .pagercontainer { margin: 20px 0; background: whitesmoke; padding: 5px; } .pager { float: right; font-size: 10pt; text-align: left; } .pagerbutton,.pagerbutton-selected,.pagertext { display: block; float: left; text-align: center; border: solid 2px maroon; min-width: 18px; margin-left: 3px; text-decoration: none; padding: 4px; } .pagerbutton-selected { font-size: 130%; font-weight: bold; color: maroon; border-width: 0px; background: khaki; } .pagerbutton-first { margin-right: 12px; } .pagerbutton-last,.pagerbutton-prev { margin-left: 12px; } .pagertext { border: none; margin-left: 30px; font-weight: bold; } .pagerbutton a { text-decoration: none; } .pagerbutton:hover { background-color: maroon; color: cornsilk; } .pagerbutton-prev { background-image: url(images/prev.png); background-position: 2px center; background-repeat: no-repeat; width: 35px; padding-left: 20px; } .pagerbutton-next { background-image: url(images/next.png); background-position: 40px center; background-repeat: no-repeat; width: 35px; padding-right: 20px; margin-right: 0px; } Yup that’s a lot of styling settings although not all of them are required. The key ones are pagerbutton, pager and pager selection. The others (which are implicitly created by the control based on the pagerbutton style) are for custom markup of the ‘special’ buttons. In my apps I tend to have two kinds of pages: Those that are associated with typical ‘grid’ displays that display purely tabular data and those that have a more looser list like layout. The two pagers shown above represent these two views and the pager and gridpager styles in my standard style sheet reflect these two styles. Configuring the Pager with Code Finally lets look at what it takes to hook up the pager. As mentioned in the highlights the Pager control is completely independent of other controls so if you just want to display a pager on its own it’s as simple as dropping the control and assigning the PageSize, ActivePage and either TotalPages or TotalItems. So for this markup: <ww:Pager runat="server" id="ItemPagerManual" PageSize="5" MaxPagesToDisplay="6" /> I can use code as simple as: ItemPagerManual.PageSize = 3; ItemPagerManual.ActivePage = 4;ItemPagerManual.TotalItems = 20; Note that ActivePage is not required - it will automatically use any Page=x query string value and assign it, although you can override it as I did above. TotalItems can be any value that you retrieve from a result set or manually assign as I did above. A more realistic scenario based on a LINQ to SQL IQueryable result is even easier. In this example, I have a UserControl that contains a ListView control that renders IQueryable data. I use a User Control here because there are different views the user can choose from with each view being a different user control. This incidentally also highlights one of the nice features of the pager: Because the pager is independent of the control I can put the pager on the host page instead of into each of the user controls. IOW, there’s only one Pager control, but there are potentially many user controls/listviews that hold the actual display data. The following code demonstrates how to use the Pager with an IQueryable that loads only the records it displays: protected voidPage_Load(objectsender, EventArgs e) {     Category = Request.Params["Category"] ?? string.Empty;     IQueryable<wws_Item> ItemList = ItemRepository.GetItemsByCategory(Category);     // Update the page and filter the list down     ItemList = ItemPager.FilterIQueryable<wws_Item>(ItemList); // Render user control with a list view Control ulItemList = LoadControl("~/usercontrols/" + App.Configuration.ItemListType + ".ascx"); ((IInventoryItemListControl)ulItemList).InventoryItemList = ItemList; phItemList.Controls.Add(ulItemList); // placeholder } The code uses a business object to retrieve Items by category as an IQueryable which means that the result is only an expression tree that hasn’t execute SQL yet and can be further filtered. I then pass this IQueryable to the FilterIQueryable() helper method of the control which does two main things: Filters the IQueryable to retrieve only the data displayed on the active page Sets the Totaltems property and calculates TotalPages on the Pager and that’s it! When the Pager renders it uses those values, plus the PageSize and ActivePage properties to render the Pager. In addition to IQueryable there are also filter methods for IEnumerable<T> and DataTable, but these versions just filter the data by removing rows/items from the entire already retrieved data. Output Generated and Paging Links The output generated creates pager links as plain href links. Here’s what the output looks like: <div id="ItemPager" class="pagercontainer"> <div class="pager"> <span class="pagertext">Pages: </span><a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=1" class="pagerbutton" />1</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=2" class="pagerbutton" />2</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=3" class="pagerbutton" />3</a> <span class="pagerbutton-selected">4</span> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=5" class="pagerbutton" />5</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=6" class="pagerbutton" />6</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=20" class="pagerbutton pagerbutton-last" />20</a>&nbsp;<a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=3" class="pagerbutton pagerbutton-prev" />Prev</a>&nbsp;<a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=5" class="pagerbutton pagerbutton-next" />Next</a></div> <br clear="all" /> </div> </div> The links point back to the current page and simply append a Page= page link into the page. When the page gets reloaded with the new page number the pager automatically detects the page number and automatically assigns the ActivePage property which results in the appropriate page to be displayed. The code shown in the previous section is all that’s needed to handle paging. Note that HTTP GET based paging is different than the Postback paging ASP.NET uses by default. Postback paging preserves modified page content when clicking on pager buttons, but this control will simply load a new page – no page preservation at this time. The advantage of not using Postback paging is that the URLs generated are plain HTML links that a search engine can follow where __doPostback() links are not. Pager with a Grid The pager also works in combination with grid controls so it’s easy to bypass the grid control’s paging features if desired. In the following example I use a gridView control and binds it to a DataTable result which is also filterable by the Pager control. The very basic plain vanilla ASP.NET grid markup looks like this: <div style="width: 600px; margin: 0 auto;padding: 20px; "> <asp:DataGrid runat="server" AutoGenerateColumns="True" ID="gdItems" CssClass="blackborder" style="width: 600px;"> <AlternatingItemStyle CssClass="gridalternate" /> <HeaderStyle CssClass="gridheader" /> </asp:DataGrid> <ww:Pager runat="server" ID="Pager" CssClass="gridpager" ContainerDivCssClass="gridpagercontainer" PageLinkCssClass="gridpagerbutton" SelectedPageCssClass="gridpagerbutton-selected" PageSize="8" RenderContainerDiv="true" MaxPagesToDisplay="6" /> </div> and looks like this when rendered: using custom set of CSS styles. The code behind for this code is also very simple: protected void Page_Load(object sender, EventArgs e) { string category = Request.Params["category"] ?? ""; busItem itemRep = WebStoreFactory.GetItem(); var items = itemRep.GetItemsByCategory(category) .Select(itm => new {Sku = itm.Sku, Description = itm.Description}); // run query into a DataTable for demonstration DataTable dt = itemRep.Converter.ToDataTable(items,"TItems"); // Remove all items not on the current page dt = Pager.FilterDataTable(dt,0); // bind and display gdItems.DataSource = dt; gdItems.DataBind(); } A little contrived I suppose since the list could already be bound from the list of elements, but this is to demonstrate that you can also bind against a DataTable if your business layer returns those. Unfortunately there’s no way to filter a DataReader as it’s a one way forward only reader and the reader is required by the DataSource to perform the bindings.  However, you can still use a DataReader as long as your business logic filters the data prior to rendering and provides a total item count (most likely as a second query). Control Creation The control itself is a pretty brute force ASP.NET control. Nothing clever about this other than some basic rendering logic and some simple calculations and update routines to determine which buttons need to be shown. You can take a look at the full code from the West Wind Web Toolkit’s Repository (note there are a few dependencies). To give you an idea how the control works here is the Render() method: /// <summary> /// overridden to handle custom pager rendering for runtime and design time /// </summary> /// <param name="writer"></param> protected override void Render(HtmlTextWriter writer) { base.Render(writer); if (TotalPages == 0 && TotalItems > 0) TotalPages = CalculateTotalPagesFromTotalItems(); if (DesignMode) TotalPages = 10; // don't render pager if there's only one page if (TotalPages < 2) return; if (RenderContainerDiv) { if (!string.IsNullOrEmpty(ContainerDivCssClass)) writer.AddAttribute("class", ContainerDivCssClass); writer.RenderBeginTag("div"); } // main pager wrapper writer.WriteBeginTag("div"); writer.AddAttribute("id", this.ClientID); if (!string.IsNullOrEmpty(CssClass)) writer.WriteAttribute("class", this.CssClass); writer.Write(HtmlTextWriter.TagRightChar + "\r\n"); // Pages Text writer.WriteBeginTag("span"); if (!string.IsNullOrEmpty(PagesTextCssClass)) writer.WriteAttribute("class", PagesTextCssClass); writer.Write(HtmlTextWriter.TagRightChar); writer.Write(this.PagesText); writer.WriteEndTag("span"); // if the base url is empty use the current URL FixupBaseUrl(); // set _startPage and _endPage ConfigurePagesToRender(); // write out first page link if (ShowFirstAndLastPageLinks && _startPage != 1) { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-first"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write("1"); writer.WriteEndTag("a"); writer.Write("&nbsp;"); } // write out all the page links for (int i = _startPage; i < _endPage + 1; i++) { if (i == ActivePage) { writer.WriteBeginTag("span"); if (!string.IsNullOrEmpty(SelectedPageCssClass)) writer.WriteAttribute("class", SelectedPageCssClass); writer.Write(HtmlTextWriter.TagRightChar); writer.Write(i.ToString()); writer.WriteEndTag("span"); } else { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, i.ToString()).TrimEnd('&'); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(i.ToString()); writer.WriteEndTag("a"); } writer.Write("\r\n"); } // write out last page link if (ShowFirstAndLastPageLinks && _endPage < TotalPages) { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, TotalPages.ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-last"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(TotalPages.ToString()); writer.WriteEndTag("a"); } // Previous link if (ShowPreviousNextLinks && !string.IsNullOrEmpty(PreviousText) && ActivePage > 1) { writer.Write("&nbsp;"); writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (ActivePage - 1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-prev"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(PreviousText); writer.WriteEndTag("a"); } // Next link if (ShowPreviousNextLinks && !string.IsNullOrEmpty(NextText) && ActivePage < TotalPages) { writer.Write("&nbsp;"); writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (ActivePage + 1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-next"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(NextText); writer.WriteEndTag("a"); } writer.WriteEndTag("div"); if (RenderContainerDiv) { if (RenderContainerDivBreak) writer.Write("<br clear=\"all\" />\r\n"); writer.WriteEndTag("div"); } } As I said pretty much brute force rendering based on the control’s property settings of which there are quite a few: You can also see the pager in the designer above. unfortunately the VS designer (both 2010 and 2008) fails to render the float: left CSS styles properly and starts wrapping after margins are applied in the special buttons. Not a big deal since VS does at least respect the spacing (the floated elements overlay). Then again I’m not using the designer anyway :-}. Filtering Data What makes the Pager easy to use is the filter methods built into the control. While this functionality is clearly not the most politically correct design choice as it violates separation of concerns, it’s very useful for typical pager operation. While I actually have filter methods that do something similar in my business layer, having it exposed on the control makes the control a lot more useful for typical databinding scenarios. Of course these methods are optional – if you have a business layer that can provide filtered page queries for you can use that instead and assign the TotalItems property manually. There are three filter method types available for IQueryable, IEnumerable and for DataTable which tend to be the most common use cases in my apps old and new. The IQueryable version is pretty simple as it can simply rely on on .Skip() and .Take() with LINQ: /// <summary> /// <summary> /// Queries the database for the ActivePage applied manually /// or from the Request["page"] variable. This routine /// figures out and sets TotalPages, ActivePage and /// returns a filtered subset IQueryable that contains /// only the items from the ActivePage. /// </summary> /// <param name="query"></param> /// <param name="activePage"> /// The page you want to display. Sets the ActivePage property when passed. /// Pass 0 or smaller to use ActivePage setting. /// </param> /// <returns></returns> public IQueryable<T> FilterIQueryable<T>(IQueryable<T> query, int activePage) where T : class, new() { ActivePage = activePage < 1 ? ActivePage : activePage; if (ActivePage < 1) ActivePage = 1; TotalItems = query.Count(); if (TotalItems <= PageSize) { ActivePage = 1; TotalPages = 1; return query; } int skip = ActivePage - 1; if (skip > 0) query = query.Skip(skip * PageSize); _TotalPages = CalculateTotalPagesFromTotalItems(); return query.Take(PageSize); } The IEnumerable<T> version simply  converts the IEnumerable to an IQuerable and calls back into this method for filtering. The DataTable version requires a little more work to manually parse and filter records (I didn’t want to add the Linq DataSetExtensions assembly just for this): /// <summary> /// Filters a data table for an ActivePage. /// /// Note: Modifies the data set permanently by remove DataRows /// </summary> /// <param name="dt">Full result DataTable</param> /// <param name="activePage">Page to display. 0 to use ActivePage property </param> /// <returns></returns> public DataTable FilterDataTable(DataTable dt, int activePage) { ActivePage = activePage < 1 ? ActivePage : activePage; if (ActivePage < 1) ActivePage = 1; TotalItems = dt.Rows.Count; if (TotalItems <= PageSize) { ActivePage = 1; TotalPages = 1; return dt; } int skip = ActivePage - 1; if (skip > 0) { for (int i = 0; i < skip * PageSize; i++ ) dt.Rows.RemoveAt(0); } while(dt.Rows.Count > PageSize) dt.Rows.RemoveAt(PageSize); return dt; } Using the Pager Control The pager as it is is a first cut I built a couple of weeks ago and since then have been tweaking a little as part of an internal project I’m working on. I’ve replaced a bunch of pagers on various older pages with this pager without any issues and have what now feels like a more consistent user interface where paging looks and feels the same across different controls. As a bonus I’m only loading the data from the database that I need to display a single page. With the preset class tags applied too adding a pager is now as easy as dropping the control and adding the style sheet for styling to be consistent – no fuss, no muss. Schweet. Hopefully some of you may find this as useful as I have or at least as a baseline to build ontop of… Resources The Pager is part of the West Wind Web & Ajax Toolkit Pager.cs Source Code (some toolkit dependencies) Westwind.css base stylesheet with .pager and .gridpager styles Pager Example Page © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

    Read the article

  • WPB .Net User Group 11/29 Meeting - Kinect SDK with Joe Healy - New Meeting Location

    - by Sam Abraham
    We are excited to share great news and updates regarding the West Palm Beach .Net User Group. Our upcoming meeting will feature Joe Healy from Microsoft as speaker for the November 29th, 2011 6:30 PM meeting.   He will be covering the Kinect SDK and answering all our questions regarding the latest Windows Phone 7 Release. We will be also raffling many valuable items as part of our usual free raffle and hope each of our members leaves with a freebie.   We are also honored to share that we will be hosting our special meeting at a new location:   PC Professor 6080 Okeechobee Blvd.,  #200 West Palm Beach, FL 33417 Phone: 561-684-3333.   This is right by the Florida Turnpike entrance on Okeechobee Blvd.   PC Professor will be also providing our free pizza/soda and some additional surprise items for this meeting to mark the debut of our meetings at their location!   We would like to use this opportunity to thank our current host, CompTec, for its generous support and for hosting us for the past 2 years and look forward to their continued support and sponsorship.   A lot of work and effort is put into hosting a meeting that we hope translates into added value and benefit for our membership. We always welcome your feedback and participation as we strive to continuously improve the group.   Special thanks to our group member, Zack Weiner, for helping us find this new location.   For more details and to register please visit: http://www.fladotnet.com/Reg.aspx?EventID=536   Hope to see you all there.   --Sam Abraham & Venkat Subramanian Site Directors – West Palm Beach .Net User Group

    Read the article

  • The Benefits of Smart Grid Business Software

    - by Sylvie MacKenzie, PMP
    Smart Grid Background What Are Smart Grids?Smart Grids use computer hardware and software, sensors, controls, and telecommunications equipment and services to: Link customers to information that helps them manage consumption and use electricity wisely. Enable customers to respond to utility notices in ways that help minimize the duration of overloads, bottlenecks, and outages. Provide utilities with information that helps them improve performance and control costs. What Is Driving Smart Grid Development? Environmental ImpactSmart Grid development is picking up speed because of the widespread interest in reducing the negative impact that energy use has on the environment. Smart Grids use technology to drive efficiencies in transmission, distribution, and consumption. As a result, utilities can serve customers’ power needs with fewer generating plants, fewer transmission and distribution assets,and lower overall generation. With the possible exception of wind farm sprawl, landscape preservation is one obvious benefit. And because most generation today results in greenhouse gas emissions, Smart Grids reduce air pollution and the potential for global climate change.Smart Grids also more easily accommodate the technical difficulties of integrating intermittent renewable resources like wind and solar into the grid, providing further greenhouse gas reductions. CostsThe ability to defer the cost of plant and grid expansion is a major benefit to both utilities and customers. Utilities do not need to use as many internal resources for traditional infrastructure project planning and management. Large T&D infrastructure expansion costs are not passed on to customers.Smart Grids will not eliminate capital expansion, of course. Transmission corridors to connect renewable generation with customers will require major near-term expenditures. Additionally, in the future, electricity to satisfy the needs of population growth and additional applications will exceed the capacity reductions available through the Smart Grid. At that point, expansion will resume—but with greater overall T&D efficiency based on demand response, load control, and many other Smart Grid technologies and business processes. Energy efficiency is a second area of Smart Grid cost saving of particular relevance to customers. The timely and detailed information Smart Grids provide encourages customers to limit waste, adopt energy-efficient building codes and standards, and invest in energy efficient appliances. Efficiency may or may not lower customer bills because customer efficiency savings may be offset by higher costs in generation fuels or carbon taxes. It is clear, however, that bills will be lower with efficiency than without it. Utility Operations Smart Grids can serve as the central focus of utility initiatives to improve business processes. Many utilities have long “wish lists” of projects and applications they would like to fund in order to improve customer service or ease staff’s burden of repetitious work, but they have difficulty cost-justifying the changes, especially in the short term. Adding Smart Grid benefits to the cost/benefit analysis frequently tips the scales in favor of the change and can also significantly reduce payback periods.Mobile workforce applications and asset management applications work together to deploy assets and then to maintain, repair, and replace them. Many additional benefits result—for instance, increased productivity and fuel savings from better routing. Similarly, customer portals that provide customers with near-real-time information can also encourage online payments, thus lowering billing costs. Utilities can and should include these cost and service improvements in the list of Smart Grid benefits. What Is Smart Grid Business Software? Smart Grid business software gathers data from a Smart Grid and uses it improve a utility’s business processes. Smart Grid business software also helps utilities provide relevant information to customers who can then use it to reduce their own consumption and improve their environmental profiles. Smart Grid Business Software Minimizes the Impact of Peak Demand Utilities must size their assets to accommodate their highest peak demand. The higher the peak rises above base demand: The more assets a utility must build that are used only for brief periods—an inefficient use of capital. The higher the utility’s risk profile rises given the uncertainties surrounding the time needed for permitting, building, and recouping costs. The higher the costs for utilities to purchase supply, because generators can charge more for contracts and spot supply during high-demand periods. Smart Grids enable a variety of programs that reduce peak demand, including: Time-of-use pricing and critical peak pricing—programs that charge customers more when they consume electricity during peak periods. Pilot projects indicate that these programs are successful in flattening peaks, thus ensuring better use of existing T&D and generation assets. Direct load control, which lets utilities reduce or eliminate electricity flow to customer equipment (such as air conditioners). Contracts govern the terms and conditions of these turn-offs. Indirect load control, which signals customers to reduce the use of on-premises equipment for contractually agreed-on time periods. Smart Grid business software enables utilities to impose penalties on customers who do not comply with their contracts. Smart Grids also help utilities manage peaks with existing assets by enabling: Real-time asset monitoring and control. In this application, advanced sensors safely enable dynamic capacity load limits, ensuring that all grid assets can be used to their maximum capacity during peak demand periods. Real-time asset monitoring and control applications also detect the location of excessive losses and pinpoint need for mitigation and asset replacements. As a result, utilities reduce outage risk and guard against excess capacity or “over-build”. Better peak demand analysis. As a result: Distribution planners can better size equipment (e.g. transformers) to avoid over-building. Operations engineers can identify and resolve bottlenecks and other inefficiencies that may cause or exacerbate peaks. As above, the result is a reduction in the tendency to over-build. Supply managers can more closely match procurement with delivery. As a result, they can fine-tune supply portfolios, reducing the tendency to over-contract for peak supply and reducing the need to resort to spot market purchases during high peaks. Smart Grids can help lower the cost of remaining peaks by: Standardizing interconnections for new distributed resources (such as electricity storage devices). Placing the interconnections where needed to support anticipated grid congestion. Smart Grid Business Software Lowers the Cost of Field Services By processing Smart Grid data through their business software, utilities can reduce such field costs as: Vegetation management. Smart Grids can pinpoint momentary interruptions and tree-caused outages. Spatial mash-up tools leverage GIS models of tree growth for targeted vegetation management. This reduces the cost of unnecessary tree trimming. Service vehicle fuel. Many utility service calls are “false alarms.” Checking meter status before dispatching crews prevents many unnecessary “truck rolls.” Similarly, crews use far less fuel when Smart Grid sensors can pinpoint a problem and mobile workforce applications can then route them directly to it. Smart Grid Business Software Ensures Regulatory Compliance Smart Grids can ensure compliance with private contracts and with regional, national, or international requirements by: Monitoring fulfillment of contract terms. Utilities can use one-hour interval meters to ensure that interruptible (“non-core”) customers actually reduce or eliminate deliveries as required. They can use the information to levy fines against contract violators. Monitoring regulations imposed on customers, such as maximum use during specific time periods. Using accurate time-stamped event history derived from intelligent devices distributed throughout the smart grid to monitor and report reliability statistics and risk compliance. Automating business processes and activities that ensure compliance with security and reliability measures (e.g. NERC-CIP 2-9). Grid Business Software Strengthens Utilities’ Connection to Customers While Reducing Customer Service Costs During outages, Smart Grid business software can: Identify outages more quickly. Software uses sensors to pinpoint outages and nested outage locations. They also permit utilities to ensure outage resolution at every meter location. Size outages more accurately, permitting utilities to dispatch crews that have the skills needed, in appropriate numbers. Provide updates on outage location and expected duration. This information helps call centers inform customers about the timing of service restoration. Smart Grids also facilitates display of outage maps for customer and public-service use. Smart Grids can significantly reduce the cost to: Connect and disconnect customers. Meters capable of remote disconnect can virtually eliminate the costs of field crews and vehicles previously required to change service from the old to the new residents of a metered property or disconnect customers for nonpayment. Resolve reports of voltage fluctuation. Smart Grids gather and report voltage and power quality data from meters and grid sensors, enabling utilities to pinpoint reported problems or resolve them before customers complain. Detect and resolve non-technical losses (e.g. theft). Smart Grids can identify illegal attempts to reconnect meters or to use electricity in supposedly vacant premises. They can also detect theft by comparing flows through delivery assets with billed consumption. Smart Grids also facilitate outreach to customers. By monitoring and analyzing consumption over time, utilities can: Identify customers with unusually high usage and contact them before they receive a bill. They can also suggest conservation techniques that might help to limit consumption. This can head off “high bill” complaints to the contact center. Note that such “high usage” or “additional charges apply because you are out of range” notices—frequently via text messaging—are already common among mobile phone providers. Help customers identify appropriate bill payment alternatives (budget billing, prepayment, etc.). Help customers find and reduce causes of over-consumption. There’s no waiting for bills in the mail before they even understand there is a problem. Utilities benefit not just through improved customer relations but also through limiting the size of bills from customers who might struggle to pay them. Where permitted, Smart Grids can open the doors to such new utility service offerings as: Monitoring properties. Landlords reduce costs of vacant properties when utilities notify them of unexpected energy or water consumption. Utilities can perform similar services for owners of vacation properties or the adult children of aging parents. Monitoring equipment. Power-use patterns can reveal a need for equipment maintenance. Smart Grids permit utilities to alert owners or managers to a need for maintenance or replacement. Facilitating home and small-business networks. Smart Grids can provide a gateway to equipment networks that automate control or let owners access equipment remotely. They also facilitate net metering, offering some utilities a path toward involvement in small-scale solar or wind generation. Prepayment plans that do not need special meters. Smart Grid Business Software Helps Customers Control Energy Costs There is no end to the ways Smart Grids help both small and large customers control energy costs. For instance: Multi-premises customers appreciate having all meters read on the same day so that they can more easily compare consumption at various sites. Customers in competitive regions can match their consumption profile (detailed via Smart Grid data) with specific offerings from competitive suppliers. Customers seeing inexplicable consumption patterns and power quality problems may investigate further. The result can be discovery of electrical problems that can be resolved through rewiring or maintenance—before more serious fires or accidents happen. Smart Grid Business Software Facilitates Use of Renewables Generation from wind and solar resources is a popular alternative to fossil fuel generation, which emits greenhouse gases. Wind and solar generation may also increase energy security in regions that currently import fossil fuel for use in generation. Utilities face many technical issues as they attempt to integrate intermittent resource generation into traditional grids, which traditionally handle only fully dispatchable generation. Smart Grid business software helps solves many of these issues by: Detecting sudden drops in production from renewables-generated electricity (wind and solar) and automatically triggering electricity storage and smart appliance response to compensate as needed. Supporting industry-standard distributed generation interconnection processes to reduce interconnection costs and avoid adding renewable supplies to locations already subject to grid congestion. Facilitating modeling and monitoring of locally generated supply from renewables and thus helping to maximize their use. Increasing the efficiency of “net metering” (through which utilities can use electricity generated by customers) by: Providing data for analysis. Integrating the production and consumption aspects of customer accounts. During non-peak periods, such techniques enable utilities to increase the percent of renewable generation in their supply mix. During peak periods, Smart Grid business software controls circuit reconfiguration to maximize available capacity. Conclusion Utility missions are changing. Yesterday, they focused on delivery of reasonably priced energy and water. Tomorrow, their missions will expand to encompass sustainable use and environmental improvement.Smart Grids are key to helping utilities achieve this expanded mission. But they come at a relatively high price. Utilities will need to invest heavily in new hardware, software, business process development, and staff training. Customer investments in home area networks and smart appliances will be large. Learning to change the energy and water consumption habits of a lifetime could ultimately prove even more formidable tasks.Smart Grid business software can ease the cost and difficulties inherent in a needed transition to a more flexible, reliable, responsive electricity grid. Justifying its implementation, however, requires a full understanding of the benefits it brings—benefits that can ultimately help customers, utilities, communities, and the world address global issues like energy security and climate change while minimizing costs and maximizing customer convenience. This white paper is available for download here. For further information about Oracle's Primavera Solutions for Utilities, please read our Utilities e-book.

    Read the article

  • Get Ready to Meet Oracle GoldenGate 11gR2 at OpenWorld

    - by Irem Radzik
      Oracle GoldenGate 11g Release 2 could not come at a better time. At Oracle OpenWorld 2012 we have a great set of sessions and demos for Oracle GoldenGate users: deep dives into the new features of Oracle GoldenGate 11gR2, as well as great customer presentations from Comcast, Bank of America, Turk Telekom, Ticketmaster, St. Jude Medical Center, and more. Here are 3 must-attend sessions for GoldenGate users and for those who want to get to know GoldenGate’s capabilities: Real-World Zero-Downtime Operations with Oracle GoldenGate: Customer Panel Oct 1st 1:45 PM Moscone West – 3005 Oracle GoldenGate 11g Release 2 New Features Oct 1st 3:15 PM Moscone West – 3005 Real-World Operational Reporting with Oracle GoldenGate: Customer Panel Oct 2nd 11:45 AM Moscone West - 3005 For a full list of GoldenGate and data integration sessions, please check out our Focus-On for Data Integration. Similar to last year, Hands-on-Labs will be available for those who want to experience the power of GoldenGate first hand. One of these instructor-led sessions provides “Deep Dive into Oracle GoldenGate” will be held on Thursday Oct 4th 11:15am at Marriott Marquis - Salon ½. I expect the spots will fill out fast in this session. Oracle GoldenGate Demos will be running Monday through Wednesday in Moscone South in both Oracle Database and Oracle Fusion Middleware sections of the Oracle demo grounds. We will be showcasing: Monitoring Oracle GoldenGate for End-to-End Visibility Oracle GoldenGate 11gR2 New Features Oracle GoldenGate 11gR2: Real-Time, Transactional Database Replication Oracle GoldenGate Veridata Oracle Maximum Availability Architecture If you are not able to attend OpenWorld, you should not miss this week’s live webcast introducing Oracle GoldenGate 11g Release 2. On Wednesday the webcast will present the new features of GoldenGate and attendees will have a long, live Q&A panel session with the PM team.  I also recommend checking out the resources for GoldenGate to download new white papers. The whole team is looking forward to sharing with you the latest and greatest features of GoldenGate at the launch webcast and at OpenWorld.

    Read the article

  • Focus on Identity Management at Oracle OpenWorld12

    - by Tanu Sood
    Heading to Oracle OpenWorld 2012? Then we have Identity Management and relevant sessions all mapped out for you to help you navigate Oracle OpenWorld. Do make use of Focus On Identity Management document online or if you’d like to have a copy handy, use the pdf version instead. In the meantime, here are the 3 must-attend Identity Management sessions for this year: Trends in Identity Management Monday, October 1, at 10:45 a.m., Moscone West L3, room 3003, (session ID# CON9405) Led by Amit Jasuja, this session focuses on how the latest release of Oracle Identity Management addresses emerging identity management requirements for mobile, social, and cloud computing. It also explores how existing Oracle Identity Management customers are simplifying implementations and reducing total cost of ownership. Mobile Access Management Tuesday, October 2, at 10:15 a.m., Moscone West L3, room 3022, (session ID# CON9437) There are now more than 5 billion mobile devices on the planet, including an increasing number of personal devices being used to access corporate data and applications. This session focuses on ways to extend your existing identity management infrastructure and policies to securely and seamlessly enable mobile user access. Evolving Identity Management Thursday, October 4, at 12:45 p.m., Moscone West L3, room 3008, (session ID# CON9640) Identity management requirements have evolved and are continuing to evolve as organizations seek to secure cloud and mobile access. This session explores emerging requirements and shares best practices for evolving your identity management implementation, including the value of a service-oriented, platform approach. For a complete listing of all identity management sessions, hands-on labs, and more, see Focus on Identity Management now. See you at OOW12. 

    Read the article

  • Thursday at OpenWorld: Identity Management

    - by Tanu Sood
    Before you know it, we are at the last day at Oracle OpenWorld. But just the same, Thursday is packed with informational, educational and networking opportunities. Here’s what is in store for you today: Thursday, October 4, 2012 CON5749: Solutions for Migration of Oracle Waveset to Oracle Identity Manager 11:15 a.m. – 12:15 p.m., Moscone West 3008 Many customers of Oracle Waveset (formerly Sun Identity Manager) are planning a migration to the strategic provisioning product Oracle Identity Manager. There are several approaches to migrating to Oracle Identity Manager. Presented by Hub City Media and Oracle, this session covers these various approaches to help you select the optimum choice for your implementation. CON9640: Evolving Identity Management 12:45 p.m. – 1:45 p.m., Moscone West 3008 Identity management requirements have evolved and are continuing to evolve as organizations seek to secure cloud and mobile access.  Customers are seeing good success reducing costs and supporting business growth with by embracing a service-oriented, platform approach to addressing identity management requirements.  This session will explore these emerging requirements and share best practices for evolving your implementation. CON9662: Securing Oracle Applications with the Oracle Enterprise Identity Management Platform 2:15 p.m. – 3:15 p.m., Moscone West 3008 Oracle Enterprise Identity Management solutions are designed to secure access and simplify compliance to Oracle Applications.  Whether you are an EBS customer looking to upgrade from Oracle Single Sign-on or a Fusion Application customer seeking to leverage the Identity instance as an enterprise security platform, this session with Qualcomm and Oracle will help you understand how to get the most out of your investment. HOL10479: Integrated Identity Governance 12:45 p.m. – 1:45 p.m., Marriott Marquis – Salon 1/2 This hands-on lab demonstrates Oracle’s integrated and self-service-oriented identity governance solution, which includes simple access request, business-user-friendly access certification, closed-loop remediation, and both standard and privileged accounts. For a complete listing, refer to the Focus on Identity Management document. And as always, you can find us on @oracleidm on twitter and FaceBook. Use #oow and #idm to join in the conversation.

    Read the article

  • Oracle Policy Automation at OpenWorld 2012

    - by jeffrey.waterman
    Oracle Policy Automation (OPA)atOpenWorld 2012 Oracle Policy Automation (OPA), the breakthrough policy automation platform, enables organizations to deliver: Consistent policy-based decision making throughout the organization across all channels Agile response to policy changes and analysis Transparency and auditability This year there will be: 8 sessions – combination of customer panels & product strategy sessions Standalone OPA DEMOpod – Moscone Center WEST, W044 Key highlights Hear Davin Fifield discuss the Product Roadmap for OPA (including OPA + RightNow) he will also be joined by Sean Haynes from Stewart Title who will share the success they are having with OPA. OPA Public Sector Customer Panel - This year the OPA panel consists of some of OPA’s most successful & largest customers, speakers include: Department Works & Pension (UK) Toll – Department of Defence (AU) Municipality of Sao Paulo (Brazil) SCHEDULE HIGHLIGHTS Monday October 1, 2012 SESSION ID TIME TITLE LOCATION CON9655 12:15 pm  1:15 pm PST (Pacific Standard Time) Oracle Policy Automation Roadmap: Supercharging the Customer Experience Davin Fifield, VP OPA Development, OracleSean Haynes, VP Stewart Title Westin San Francisco - Metropolitan I CON9700 12:15 m – 1:15 pm PST (Pacific Standard Time) Siebel CRM Overview, Strategy, and RoadmapGeorge Jacob - Group Vice President, CRM Applications / XML, OracleUma Welingkar - Director, Product Management, Oracle Moscone West - 2009 Wednesday October 3, 2012 SESSION ID TIME TITLE LOCATION CON8840 5.00pm – 6.00pm PST (Pacific Standard Time) Achieving Agility Through Closed-Loop Policy AutomationCustomer PanelFacilitator – Surend Dayal, Oracle Dept. Works & Pension (UK) – Haydn Leary Municipality of Sao Paulo (Brazil) - Luiz Cesar Michielin Kiel Toll (AU) – Nigel Maloney   Westin San Francisco - Franciscan I CON8952 5.00pm – 6.00pm PST (Pacific Standard Time) BPM: An Extension Strategy for Enterprise ApplicationsHarish Gaur -  OracleSrikant Subramaniam - Oracle Moscone West - 3003 Thursday October 4, 2012 SESSION ID TIME TITLE LOCATION CON11515 2:15 pm – 3:15 pm PST (Pacific Standard Time) Oracle Policy Automation + RightNow: Agile self-service and agent experiencesDavin Fifield, VP OPA Development, Oracle Westin San Francisco - City

    Read the article

  • More on Oracle OpenWorld 2012

    - by Maria Colgan
    With only two weeks to go until Oracle OpenWorld, it is time to start planning your schedule. Every year folks ask me what Optimizer related sessions they should go and see at OpenWorld. Below are my top two picks for each day of the conference, to get your schedule started. Sunday, September 30th at 9am Beginning performance tuning Session UGF 3320 in Moscone West, room 2022 Sunday September 30th at 12:30pm Ten Surprising Performance Tactics Session UGF10426 in Moscone West, room 2016 Monday October 1st at 12:15pm The Evolution of Histograms in Oracle Database Session CON2803 in Moscone south, room 302 Monday October 1st at 1:45pm A Day in the Life of a Real-World Performance Engineer Session CON8404 in Moscone south, room 303 Tuesday October 2nd at 11:45am Oracle Partitioning: It’s Getting Even Better Session CON8321 in Moscone South, room 101 Tuesday October 2nd at 1:15pm Oracle Optimizer: Harnessing the Power of Optimizer Hints  Session CON8455 in Moscone South, room 103 Wednesday October 3rd at 3:30pm SQL Plan Stability: Post 11g Upgrade—Verizon Wireless’ Experience Session CON4485 in Moscone South, room 302 Wednesday October 3rd at 5pm Five SQL and PL/SQL Things in the Latest Generation of Database Technology Session CON8432 Moscone South, room 103 Thursday, October 4th at 11:15pm How the Query Optimizer Learns from Its Mistakes  Session CON3330 in Moscone west, room 3016 Thursday, October 4th at 12:45pm Oracle Optimizer: An Insider’s View of How the Optimizer Works Session CON8457 in Moscone South, room 104 Don't forget to pickup an Optimizer bumper sticker at the Optimizer demo booth. This year we are located in booth 3157, in the Database area of the demogrounds, in Moscone South. Members of the Optimizer development team will be there Monday through Wednesday from 9:45 am until 6pm.

    Read the article

  • The dynamic Type in C# Simplifies COM Member Access from Visual FoxPro

    - by Rick Strahl
    I’ve written quite a bit about Visual FoxPro interoperating with .NET in the past both for ASP.NET interacting with Visual FoxPro COM objects as well as Visual FoxPro calling into .NET code via COM Interop. COM Interop with Visual FoxPro has a number of problems but one of them at least got a lot easier with the introduction of dynamic type support in .NET. One of the biggest problems with COM interop has been that it’s been really difficult to pass dynamic objects from FoxPro to .NET and get them properly typed. The only way that any strong typing can occur in .NET for FoxPro components is via COM type library exports of Visual FoxPro components. Due to limitations in Visual FoxPro’s type library support as well as the dynamic nature of the Visual FoxPro language where few things are or can be described in the form of a COM type library, a lot of useful interaction between FoxPro and .NET required the use of messy Reflection code in .NET. Reflection is .NET’s base interface to runtime type discovery and dynamic execution of code without requiring strong typing. In FoxPro terms it’s similar to EVALUATE() functionality albeit with a much more complex API and corresponiding syntax. The Reflection APIs are fairly powerful, but they are rather awkward to use and require a lot of code. Even with the creation of wrapper utility classes for common EVAL() style Reflection functionality dynamically access COM objects passed to .NET often is pretty tedious and ugly. Let’s look at a simple example. In the following code I use some FoxPro code to dynamically create an object in code and then pass this object to .NET. An alternative to this might also be to create a new object on the fly by using SCATTER NAME on a database record. How the object is created is inconsequential, other than the fact that it’s not defined as a COM object – it’s a pure FoxPro object that is passed to .NET. Here’s the code: *** Create .NET COM InstanceloNet = CREATEOBJECT('DotNetCom.DotNetComPublisher') *** Create a Customer Object Instance (factory method) loCustomer = GetCustomer() loCustomer.Name = "Rick Strahl" loCustomer.Company = "West Wind Technologies" loCustomer.creditLimit = 9999999999.99 loCustomer.Address.StreetAddress = "32 Kaiea Place" loCustomer.Address.Phone = "808 579-8342" loCustomer.Address.Email = "[email protected]" *** Pass Fox Object and echo back values ? loNet.PassRecordObject(loObject) RETURN FUNCTION GetCustomer LOCAL loCustomer, loAddress loCustomer = CREATEOBJECT("EMPTY") ADDPROPERTY(loCustomer,"Name","") ADDPROPERTY(loCustomer,"Company","") ADDPROPERTY(loCUstomer,"CreditLimit",0.00) ADDPROPERTY(loCustomer,"Entered",DATETIME()) loAddress = CREATEOBJECT("Empty") ADDPROPERTY(loAddress,"StreetAddress","") ADDPROPERTY(loAddress,"Phone","") ADDPROPERTY(loAddress,"Email","") ADDPROPERTY(loCustomer,"Address",loAddress) RETURN loCustomer ENDFUNC Now prior to .NET 4.0 you’d have to access this object passed to .NET via Reflection and the method code to do this would looks something like this in the .NET component: public string PassRecordObject(object FoxObject) { // *** using raw Reflection string Company = (string) FoxObject.GetType().InvokeMember( "Company", BindingFlags.GetProperty,null, FoxObject,null); // using the easier ComUtils wrappers string Name = (string) ComUtils.GetProperty(FoxObject,"Name"); // Getting Address object – then getting child properties object Address = ComUtils.GetProperty(FoxObject,"Address");    string Street = (string) ComUtils.GetProperty(FoxObject,"StreetAddress"); // using ComUtils 'Ex' functions you can use . Syntax     string StreetAddress = (string) ComUtils.GetPropertyEx(FoxObject,"AddressStreetAddress"); return Name + Environment.NewLine + Company + Environment.NewLine + StreetAddress + Environment.NewLine + " FOX"; } Note that the FoxObject is passed in as type object which has no specific type. Since the object doesn’t exist in .NET as a type signature the object is passed without any specific type information as plain non-descript object. To retrieve a property the Reflection APIs like Type.InvokeMember or Type.GetProperty().GetValue() etc. need to be used. I made this code a little simpler by using the Reflection Wrappers I mentioned earlier but even with those ComUtils calls the code is pretty ugly requiring passing the objects for each call and casting each element. Using .NET 4.0 Dynamic Typing makes this Code a lot cleaner Enter .NET 4.0 and the dynamic type. Replacing the input parameter to the .NET method from type object to dynamic makes the code to access the FoxPro component inside of .NET much more natural: public string PassRecordObjectDynamic(dynamic FoxObject) { // *** using raw Reflection string Company = FoxObject.Company; // *** using the easier ComUtils class string Name = FoxObject.Name; // *** using ComUtils 'ex' functions to use . Syntax string Address = FoxObject.Address.StreetAddress; return Name + Environment.NewLine + Company + Environment.NewLine + Address + Environment.NewLine + " FOX"; } As you can see the parameter is of type dynamic which as the name implies performs Reflection lookups and evaluation on the fly so all the Reflection code in the last example goes away. The code can use regular object ‘.’ syntax to reference each of the members of the object. You can access properties and call methods this way using natural object language. Also note that all the type casts that were required in the Reflection code go away – dynamic types like var can infer the type to cast to based on the target assignment. As long as the type can be inferred by the compiler at compile time (ie. the left side of the expression is strongly typed) no explicit casts are required. Note that although you get to use plain object syntax in the code above you don’t get Intellisense in Visual Studio because the type is dynamic and thus has no hard type definition in .NET . The above example calls a .NET Component from VFP, but it also works the other way around. Another frequent scenario is an .NET code calling into a FoxPro COM object that returns a dynamic result. Assume you have a FoxPro COM object returns a FoxPro Cursor Record as an object: DEFINE CLASS FoxData AS SESSION OlePublic cAppStartPath = "" FUNCTION INIT THIS.cAppStartPath = ADDBS( JustPath(Application.ServerName) ) SET PATH TO ( THIS.cAppStartpath ) ENDFUNC FUNCTION GetRecord(lnPk) LOCAL loCustomer SELECT * FROM tt_Cust WHERE pk = lnPk ; INTO CURSOR TCustomer IF _TALLY < 1 RETURN NULL ENDIF SCATTER NAME loCustomer MEMO RETURN loCustomer ENDFUNC ENDDEFINE If you call this from a .NET application you can now retrieve this data via COM Interop and cast the result as dynamic to simplify the data access of the dynamic FoxPro type that was created on the fly: int pk = 0; int.TryParse(Request.QueryString["id"],out pk); // Create Fox COM Object with Com Callable Wrapper FoxData foxData = new FoxData(); dynamic foxRecord = foxData.GetRecord(pk); string company = foxRecord.Company; DateTime entered = foxRecord.Entered; This code looks simple and natural as it should be – heck you could write code like this in days long gone by in scripting languages like ASP classic for example. Compared to the Reflection code that previously was necessary to run similar code this is much easier to write, understand and maintain. For COM interop and Visual FoxPro operation dynamic type support in .NET 4.0 is a huge improvement and certainly makes it much easier to deal with FoxPro code that calls into .NET. Regardless of whether you’re using COM for calling Visual FoxPro objects from .NET (ASP.NET calling a COM component and getting a dynamic result returned) or whether FoxPro code is calling into a .NET COM component from a FoxPro desktop application. At one point or another FoxPro likely ends up passing complex dynamic data to .NET and for this the dynamic typing makes coding much cleaner and more readable without having to create custom Reflection wrappers. As a bonus the dynamic runtime that underlies the dynamic type is fairly efficient in terms of making Reflection calls especially if members are repeatedly accessed. © Rick Strahl, West Wind Technologies, 2005-2010Posted in COM  FoxPro  .NET  CSharp  

    Read the article

  • Make your CHM Help Files show HTML5 and CSS3 content

    - by Rick Strahl
    The HTML Help 1.0 specification aka CHM files, is pretty old. In fact, it's practically ancient as it was introduced in 1997 when Internet Explorer 4 was introduced. Html Help 1.0 is basically a completely HTML based Help system that uses a Help Viewer that internally uses Internet Explorer to render the HTML Help content. Because of its use of the Internet Explorer shell for rendering there were many security issues in the past, which resulted in locking down of the Web Browser control in Windows and also the Help Engine which caused some unfortunate side effects. Even so, CHM continues to be a popular help format because it is very easy to produce content for it, using plain HTML and because it works with many Windows application platforms out of the box. While there have been various attempts to replace CHM help files CHM files still seem to be a popular choice for many applications to display their help systems. The biggest alternative these days is no system based help at all, but links to online documentation. For Windows apps though it's still very common to see CHM help files and there are still a ton of CHM help out there and lots of tools (including our own West Wind Html Help Builder) that produce output for CHM files as well as Web output. Image is Everything and you ain't got it! One problem with the CHM engine is that it's stuck with an ancient Internet Explorer version for rendering. For example if you have help content that uses HTML5 or CSS3 content you might have an HTML Help topic like the following shown here in a full Web Browser instance of Internet Explorer: The page clearly uses some CSS3 features like rounded corners and box shadows that are rendered using plain CSS 3 features. Note that I used Internet Explorer on purpose here to demonstrate that IE9 on Windows 7 can properly render this content using some of the new features of CSS, but the same is true for all other recent versions of the major browsers (FireFox 3.1+, Safari 4.5+, WebKit 9+ etc.). Unfortunately if you take this nice and simple CSS3 content and run it through the HTML Help compiler to produce a CHM file the resulting output on the same machine looks a bit less flashy: All the CSS3 styling is gone and although the page display and functionality still works, but all the extra styling features are gone. This even though I am running this on a Windows 7 machine that has IE9 that should be able to render these CSS features. Bummer. Web Browser Control - perpetually stuck in IE 7 Mode The problem is the Web Browser/Shell Components in Windows. This component is and has been part of Windows for as long as Internet Explorer has been around, but the Web Browser control hasn't kept up with the latest versions of IE. In a nutshell the control is stuck in IE7 rendering mode for engine compatibility reasons by default. However, there is at least one way to fix this explicitly using Registry keys on a per application basis. The key point from that blog article is that you can override the IE rendering engine for a particular executable by setting one (or more) registry flags that tell the Windows Shell which version of the Internet Explorer rendering engine to load. An application that wishes to use a more recent version of Internet Explorer can then register itself during installation for the specific IE version desired and from then on the application will use that version of the Web Browser component. If the application is older than the specified version it falls back to the default version (IE 7 rendering). Forcing CHM files to display with IE9 (or later) Rendering Knowing that we can force the IE usage for a given process it's also possible to affect the CHM rendering by setting same keys on the executable that's hosting the CHM file. What that executable file is depends on the type of application as there are a number of ways that can launch the help engine. hh.exeThe standalone Windows CHM Help Viewer that launches when you launch a CHM from Windows Explorer. You can manually add hh.exe to the registry keys. YourApplication.exeIf you're using .NET or any tool that internally uses the hhControl ActiveX control to launch help content your application is your host. You should add your application's exe to the registry during application startup. foxhhelp9.exeIf you're building a FoxPro application that uses the built-in help features, foxhhelp9.exe is used to actually host the help controls. Make sure to add this executable to the registry. What to set You can configure the Internet Explorer version used for an application in the registry by specifying the executable file name and a value that specifies the IE version desired. There are two different sets of keys for 32 bit and 64 bit applications. 32 bit only or 64 bit: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_BROWSER_EMULATION Value Key: hh.exe 32 bit on 64 bit machine: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_BROWSER_EMULATION Value Key: hh.exe Note that it's best to always set both values ideally when you install your application so it works regardless of which platform you run on. The value specified is a DWORD value and the interesting values are decimal 9000 for IE9 rendering mode depending on !DOCTYPE settings or 9999 for IE 9 standards mode always. You can use the same logic for 8000 and 8888 for IE8 and the final value of 7000 for IE7 (one has to wonder what they're going todo for version 10 to perpetuate that pattern). I think 9000 is the value you'd most likely want to use. 9000 means that IE9 will be used for rendering but unless the right doctypes are used (XHTML and HTML5 specifically) IE will still fall back into quirks mode as needed. This should allow existing pages to continue to use the fallback engine while new pages that have the proper HTML doctype set can take advantage of the newest features. Here's an example of how I set the registry keys in my Tarma Installmate registry configuration: Note that I set all three values both under the Software and Wow6432Node keys so that this works regardless of where these EXEs are launched from. Even though all apps are 32 bit apps, the 64 bit (the default one shown selected) key is often used. So, now once I've set the registry key for hh.exe I can now launch my CHM help file from Explorer and see the following CSS3 IE9 rendered display: Summary It sucks that we have to go through all these hoops to get what should be natural behavior for an application to support the latest features available on a system. But it shouldn't be a surprise - the Windows Help team (if there even is such a thing) has not been known for forward looking technologies. It's a pretty big hassle that we have to resort to setting registry keys in order to get the Web Browser control and the internal CHM engine to render itself properly but at least it's possible to make it work after all. Using this technique it's possible to ship an application with a help file and allow your CHM help to display with richer CSS markup and correct rendering using the stricter and more consistent XHTML or HTML5 doctypes. If you provide both Web help and in-application help (and why not if you're building from a single source) you now can side step the issue of your customers asking: Why does my help file look so much shittier than the online help… No more!© Rick Strahl, West Wind Technologies, 2005-2012Posted in HTML5  Help  Html Help Builder  Internet Explorer  Windows   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • RequestValidation Changes in ASP.NET 4.0

    - by Rick Strahl
    There’s been a change in the way the ValidateRequest attribute on WebForms works in ASP.NET 4.0. I noticed this today while updating a post on my WebLog all of which contain raw HTML and so all pretty much trigger request validation. I recently upgraded this app from ASP.NET 2.0 to 4.0 and it’s now failing to update posts. At first this was difficult to track down because of custom error handling in my app – the custom error handler traps the exception and logs it with only basic error information so the full detail of the error was initially hidden. After some more experimentation in development mode the error that occurs is the typical ASP.NET validate request error (‘A potentially dangerous Request.Form value was detetected…’) which looks like this in ASP.NET 4.0: At first when I got this I was real perplexed as I didn’t read the entire error message and because my page does have: <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="NewEntry.aspx.cs" Inherits="Westwind.WebLog.NewEntry" MasterPageFile="~/App_Templates/Standard/AdminMaster.master" ValidateRequest="false" EnableEventValidation="false" EnableViewState="false" %> WTF? ValidateRequest would seem like it should be enough, but alas in ASP.NET 4.0 apparently that setting alone is no longer enough. Reading the fine print in the error explains that you need to explicitly set the requestValidationMode for the application back to V2.0 in web.config: <httpRuntime executionTimeout="300" requestValidationMode="2.0" /> Kudos for the ASP.NET team for putting up a nice error message that tells me how to fix this problem, but excuse me why the heck would you change this behavior to require an explicit override to an optional and by default disabled page level switch? You’ve just made a relatively simple fix to a solution a nasty morass of hard to discover configuration settings??? The original way this worked was perfectly discoverable via attributes in the page. Now you can set this setting in the page and get completely unexpected behavior and you are required to set what effectively amounts to a backwards compatibility flag in the configuration file. It turns out the real reason for the .config flag is that the request validation behavior has moved from WebForms pipeline down into the entire ASP.NET/IIS request pipeline and is now applied against all requests. Here’s what the breaking changes page from Microsoft says about it: The request validation feature in ASP.NET provides a certain level of default protection against cross-site scripting (XSS) attacks. In previous versions of ASP.NET, request validation was enabled by default. However, it applied only to ASP.NET pages (.aspx files and their class files) and only when those pages were executing. In ASP.NET 4, by default, request validation is enabled for all requests, because it is enabled before the BeginRequest phase of an HTTP request. As a result, request validation applies to requests for all ASP.NET resources, not just .aspx page requests. This includes requests such as Web service calls and custom HTTP handlers. Request validation is also active when custom HTTP modules are reading the contents of an HTTP request. As a result, request validation errors might now occur for requests that previously did not trigger errors. To revert to the behavior of the ASP.NET 2.0 request validation feature, add the following setting in the Web.config file: <httpRuntime requestValidationMode="2.0" /> However, we recommend that you analyze any request validation errors to determine whether existing handlers, modules, or other custom code accesses potentially unsafe HTTP inputs that could be XSS attack vectors. Ok, so ValidateRequest of the form still works as it always has but it’s actually the ASP.NET Event Pipeline, not WebForms that’s throwing the above exception as request validation is applied to every request that hits the pipeline. Creating the runtime override removes the HttpRuntime checking and restores the WebForms only behavior. That fixes my immediate problem but still leaves me wondering especially given the vague wording of the above explanation. One thing that’s missing in the description is above is one important detail: The request validation is applied only to application/x-www-form-urlencoded POST content not to all inbound POST data. When I first read this this freaked me out because it sounds like literally ANY request hitting the pipeline is affected. To make sure this is not really so I created a quick handler: public class Handler1 : IHttpHandler { public void ProcessRequest(HttpContext context) { context.Response.ContentType = "text/plain"; context.Response.Write("Hello World <hr>" + context.Request.Form.ToString()); } public bool IsReusable { get { return false; } } } and called it with Fiddler by posting some XML to the handler using a default form-urlencoded POST content type: and sure enough – hitting the handler also causes the request validation error and 500 server response. Changing the content type to text/xml effectively fixes the problem however, bypassing the request validation filter so Web Services/AJAX handlers and custom modules/handlers that implement custom protocols aren’t affected as long as they work with special input content types. It also looks that multipart encoding does not trigger event validation of the runtime either so this request also works fine: POST http://rasnote/weblog/handler1.ashx HTTP/1.1 Content-Type: multipart/form-data; boundary=------7cf2a327f01ae User-Agent: West Wind Internet Protocols 5.53 Host: rasnote Content-Length: 40 Pragma: no-cache <xml>asdasd</xml>--------7cf2a327f01ae *That* probably should trigger event validation – since it is a potential HTML form submission, but it doesn’t. New Runtime Feature, Global Scope Only? Ok, so request validation is now a runtime feature but sadly it’s a feature that’s scoped to the ASP.NET Runtime – effective scope to the entire running application/app domain. You can still manually force validation using Request.ValidateInput() which gives you the option to do this in code, but that realistically will only work with the requestValidationMode set to V2.0 as well since the 4.0 mode auto-fires before code ever gets a chance to intercept the call. Given all that, the new setting in ASP.NET 4.0 seems to limit options and makes things more difficult and less flexible. Of course Microsoft gets to say ASP.NET is more secure by default because of it but what good is that if you have to turn off this flag the very first time you need to allow one single request that bypasses request validation??? This is really shortsighted design… <sigh>© Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

    Read the article

  • No Preview Images in File Open Dialogs on Windows 7

    - by Rick Strahl
    I’ve been updating some file uploader code in my photoalbum today and while I was working with the uploader I noticed that the File Open dialog using Silverlight that handles the file selections didn’t allow me to ever see an image preview for image files. It sure would be nice if I could preview the images I’m about to upload before selecting them from a list. Here’s what my list looked like: This is the Medium Icon view, but regardless of the views available including Content view only icons are showing up. Silverlight uses the standard Windows File Open Dialog so it uses all the same settings that apply to Explorer when displaying content. It turns out that the Customization options in particular are the problem here. Specifically the Always show icons, never thumbnails option: I had this option checked initially, because it’s one of the defenses against runaway random Explorer views that never stay set at my preferences. Alas, while this setting affects Explorer views apparently it also affects all dialog based views in the same way. Unchecking the option above brings back full thumbnailing for all content and icon views. Here’s the same Medium Icon view after turning the option off: which obviously works a whole lot better for selection of images. The bummer of this is that it’s not controllable at the dialog level – at least not in Silverlight. Dialogs obviously have different requirements than what you see in Explorer so the global configuration is a bit extreme especially when there are no overrides on the dialog interface. Certainly for Silverlight the ability to have previews is a key feature for many applications since it will be dealing with lots of media content most likely. Hope this helps somebody out. Thanks to Tim Heuer who helped me track this down on Twitter.© Rick Strahl, West Wind Technologies, 2005-2010Posted in Silverlight  Windows  

    Read the article

  • Set-Cookie Headers getting stripped in ASP.NET HttpHandlers

    - by Rick Strahl
    Yikes, I ran into a real bummer of an edge case yesterday in one of my older low level handler implementations (for West Wind Web Connection in this case). Basically this handler is a connector for a backend Web framework that creates self contained HTTP output. An ASP.NET Handler captures the full output, and then shoves the result down the ASP.NET Response object pipeline writing out the content into the Response.OutputStream and seperately sending the HttpHeaders in the Response.Headers collection. The headers turned out to be the problem and specifically Http Cookies, which for some reason ended up getting stripped out in some scenarios. My handler works like this: Basically the HTTP response from the backend app would return a full set of HTTP headers plus the content. The ASP.NET handler would read the headers one at a time and then dump them out via Response.AppendHeader(). But I found that in some situations Set-Cookie headers sent along were simply stripped inside of the Http Handler. After a bunch of back and forth with some folks from Microsoft (thanks Damien and Levi!) I managed to pin this down to a very narrow edge scenario. It's easiest to demonstrate the problem with a simple example HttpHandler implementation. The following simulates the very much simplified output generation process that fails in my handler. Specifically I have a couple of headers including a Set-Cookie header and some output that gets written into the Response object.using System.Web; namespace wwThreads { public class Handler : IHttpHandler { /* NOTE: * * Run as a web.config set handler (see entry below) * * Best way is to look at the HTTP Headers in Fiddler * or Chrome/FireBug/IE tools and look for the * WWHTREADSID cookie in the outgoing Response headers * ( If the cookie is not there you see the problem! ) */ public void ProcessRequest(HttpContext context) { HttpRequest request = context.Request; HttpResponse response = context.Response; // If ClearHeaders is used Set-Cookie header gets removed! // if commented header is sent... response.ClearHeaders(); response.ClearContent(); // Demonstrate that other headers make it response.AppendHeader("RequestId", "asdasdasd"); // This cookie gets removed when ClearHeaders above is called // When ClearHEaders is omitted above the cookie renders response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); // *** This always works, even when explicit // Set-Cookie above fails and ClearHeaders is called //response.Cookies.Add(new HttpCookie("WWTHREADSID", "ThisIsTheValue")); response.Write(@"Output was created.<hr/> Check output with Fiddler or HTTP Proxy to see whether cookie was sent."); } public bool IsReusable { get { return false; } } } } In order to see the problem behavior this code has to be inside of an HttpHandler, and specifically in a handler defined in web.config with: <add name=".ck_handler" path="handler.ck" verb="*" type="wwThreads.Handler" preCondition="integratedMode" /> Note: Oddly enough this problem manifests only when configured through web.config, not in an ASHX handler, nor if you paste that same code into an ASPX page or MVC controller. What's the problem exactly? The code above simulates the more complex code in my live handler that picks up the HTTP response from the backend application and then peels out the headers and sends them one at a time via Response.AppendHeader. One of the headers in my app can be one or more Set-Cookie. I found that the Set-Cookie headers were not making it into the Response headers output. Here's the Chrome Http Inspector trace: Notice, no Set-Cookie header in the Response headers! Now, running the very same request after removing the call to Response.ClearHeaders() command, the cookie header shows up just fine: As you might expect it took a while to track this down. At first I thought my backend was not sending the headers but after closer checks I found that indeed the headers were set in the backend HTTP response, and they were indeed getting set via Response.AppendHeader() in the handler code. Yet, no cookie in the output. In the simulated example the problem is this line:response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); which in my live code is more dynamic ( ie. AppendHeader(token[0],token[1[]) )as it parses through the headers. Bizzaro Land: Response.ClearHeaders() causes Cookie to get stripped Now, here is where it really gets bizarre: The problem occurs only if: Response.ClearHeaders() was called before headers are added It only occurs in Http Handlers declared in web.config Clearly this is an edge of an edge case but of course - knowing my relationship with Mr. Murphy - I ended up running smack into this problem. So in the code above if you remove the call to ClearHeaders(), the cookie gets set!  Add it back in and the cookie is not there. If I run the above code in an ASHX handler it works. If I paste the same code (with a Response.End()) into an ASPX page, or MVC controller it all works. Only in the HttpHandler configured through Web.config does it fail! Cue the Twilight Zone Music. Workarounds As is often the case the fix for this once you know the problem is not too difficult. The difficulty lies in tracking inconsistencies like this down. Luckily there are a few simple workarounds for the Cookie issue. Don't use AppendHeader for Cookies The easiest and obvious solution to this problem is simply not use Response.AppendHeader() to set Cookies. Duh! Under normal circumstances in application level code there's rarely a reason to write out a cookie like this:response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); but rather create the cookie using the Response.Cookies collection:response.Cookies.Add(new HttpCookie("WWTHREADSID", "ThisIsTheValue")); Unfortunately, in my case where I dynamically read headers from the original output and then dynamically  write header key value pairs back  programmatically into the Response.Headers collection, I actually don't look at each header specifically so in my case the cookie is just another header. My first thought was to simply trap for the Set-Cookie header and then parse out the cookie and create a Cookie object instead. But given that cookies can have a lot of different options this is not exactly trivial, plus I don't really want to fuck around with cookie values which can be notoriously brittle. Don't use Response.ClearHeaders() The real mystery in all this is why calling Response.ClearHeaders() prevents a cookie value later written with Response.AppendHeader() to fail. I fired up Reflector and took a quick look at System.Web and HttpResponse.ClearHeaders. There's all sorts of resetting going on but nothing that seems to indicate that headers should be removed later on in the request. The code in ClearHeaders() does access the HttpWorkerRequest, which is the low level interface directly into IIS, and so I suspect it's actually IIS that's stripping the headers and not ASP.NET, but it's hard to know. Somebody from Microsoft and the IIS team would have to comment on that. In my application it's probably safe to simply skip ClearHeaders() in my handler. The ClearHeaders/ClearContent was mainly for safety but after reviewing my code there really should never be a reason that headers would be set prior to this method firing. However, if for whatever reason headers do need to be cleared, it's easy enough to manually clear the headers out:private void RemoveHeaders(HttpResponse response) { List<string> headers = new List<string>(); foreach (string header in response.Headers) { headers.Add(header); } foreach (string header in headers) { response.Headers.Remove(header); } response.Cookies.Clear(); } Now I can replace the call the Response.ClearHeaders() and I don't get the funky side-effects from Response.ClearHeaders(). Summary I realize this is a total edge case as this occurs only in HttpHandlers that are manually configured. It looks like you'll never run into this in any of the higher level ASP.NET frameworks or even in ASHX handlers - only web.config defined handlers - which is really, really odd. After all those frameworks use the same underlying ASP.NET architecture. Hopefully somebody from Microsoft has an idea what crazy dependency was triggered here to make this fail. IAC, there are workarounds to this should you run into it, although I bet when you do run into it, it'll likely take a bit of time to find the problem or even this post in a search because it's not easily to correlate the problem to the solution. It's quite possible that more than cookies are affected by this behavior. Searching for a solution I read a few other accounts where headers like Referer were mysteriously disappearing, and it's possible that something similar is happening in those cases. Again, extreme edge case, but I'm writing this up here as documentation for myself and possibly some others that might have run into this. © Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET   IIS7   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • Debugging .NET 2.0 assembly from unmanaged code in VS2010?

    - by Rick Strahl
    I’ve run into a serious snag trying to debug a .NET 2.0 assembly that is called from unmanaged code in Visual Studio 2010. I maintain a host of components that using COM interop and custom .NET runtime hosting and ever since installing Visual Studio 2010 I’ve been utterly blocked by VS 2010’s inability to apparently debug .NET 2.0 assemblies when launching through unmanaged code. Here’s what I’m actually doing (simplified scenario to demonstrate): I have a .NET 2.0 assembly that is compiled for COM Interop Compile project with .NET 2.0 target and register for COM Interop Set a breakpoint in the .NET component in one of the class methods Instantiate the .NET component via COM interop and call method The result is that the COM call works fine but the debugger never triggers on the breakpoint. If I now take that same assembly and target it at .NET 4.0 without any other changes everything works as expected – the breakpoint set in the assembly project triggers just fine. The easy answer to this problem seems to be “Just switch to .NET 4.0” but unfortunately the application and the way the runtime is actually hosted has a few complications. Specifically the runtime hosting uses .NET 2.0 hosting and apparently the only reliable way to host the .NET 4.0 runtime is to use the new hosting APIs that are provided only with .NET 4.0 (which all by itself is lame, lame, lame as once again the promise of backwards compatibility is broken once again by .NET). So for the moment I need to continue using the .NET 2.0 hosting APIs due to application requirements. I’ve been searching high and low and experimenting back and forth, posted a few questions on the MSDN forums but haven’t gotten any hints on what might be causing the apparent failure of Visual Studio 2010 to debug my .NET 2.0 assembly properly when called from un-managed code. Incidentally debugging .NET 2.0 targeted assemblies works fine when running with a managed startup application – it seems the issue is specific to the unmanaged code starting up. My particular issue is with custom runtime hosting which at first I thought was the problem. But the same issue manifests when using COM Interop against a .NET 2.0 assembly, so the hosting is probably not the issue. Curious if anybody has any ideas on what could be causing the lack of debugging in this scenario?© Rick Strahl, West Wind Technologies, 2005-2010

    Read the article

  • jQuery CSS Property Monitoring Plug-in updated

    - by Rick Strahl
    A few weeks back I had talked about the need to watch properties of an object and be able to take action when certain values changed. The need for this arose out of wanting to build generic components that could 'attach' themselves to other objects. One example is a drop shadow - if I add a shadow behavior to an object I want the shadow to be pinned to that object so when that object moves I also want the shadow to move with it, or when the panel is hidden the shadow should hide with it - automatically without having to explicitly hook up monitoring code to the panel. For example, in my shadow plug-in I can now do something like this (where el is the element that has the shadow attached and sh is the shadow): if (!exists) // if shadow was created el.watch("left,top,width,height,display", function() { if (el.is(":visible")) $(this).shadow(opt); // redraw else sh.hide(); }, 100, "_shadowMove"); The code now monitors several properties and if any of them change the provided function is called. So when the target object is moved or hidden or resized the watcher function is called and the shadow can be redrawn or hidden in the case of visibility going away. So if you run any of the following code: $("#box") .shadow() .draggable({ handle: ".blockheader" }); // drag around the box - shadow should follow // hide the box - shadow should disappear with box setTimeout(function() { $("#box").hide(); }, 4000); // show the box - shadow should come back too setTimeout(function() { $("#box").show(); }, 8000); This can be very handy functionality when you're dealing with objects or operations that you need to track generically and there are no native events for them. For example, with a generic shadow object that attaches itself to any another element there's no way that I know of to track whether the object has been moved or hidden either via some UI operation (like dragging) or via code. While some UI operations like jQuery.ui.draggable would allow events to fire when the mouse is moved nothing of the sort exists if you modify locations in code. Even tracking the object in drag mode this is hardly generic behavior - a generic shadow implementation can't know when dragging is hooked up. So the watcher provides an alternative that basically gives an Observer like pattern that notifies you when something you're interested in changes. In the watcher hookup code (in the shadow() plugin) above  a check is made if the object is visible and if it is the shadow is redrawn. Otherwise the shadow is hidden. The first parameter is a list of CSS properties to be monitored followed by the function that is called. The function called receives this as the element that's been changed and receives two parameters: The array of watched objects with their current values, plus an index to the object that caused the change function to fire. How does it work When I wrote it about this last time I started out with a simple timer that would poll for changes at a fixed interval with setInterval(). A few folks commented that there are is a DOM API - DOMAttrmodified in Mozilla and propertychange in IE that allow notification whenever any property changes which is much more efficient and smooth than the setInterval approach I used previously. On browser that support these events (FireFox and IE basically - WebKit has the DOMAttrModified event but it doesn't appear to work) the shadow effect is instant - no 'drag behind' of the shadow. Running on a browser that doesn't support still uses setInterval() and the shadow movement is slightly delayed which looks sloppy. There are a few additional changes to this code - it also supports monitoring multiple CSS properties now so a single object can monitor a host of CSS properties rather than one object per property which is easier to work with. For display purposes position, bounds and visibility will be common properties that are to be watched. Here's what the new version looks like: $.fn.watch = function (props, func, interval, id) { /// <summary> /// Allows you to monitor changes in a specific /// CSS property of an element by polling the value. /// when the value changes a function is called. /// The function called is called in the context /// of the selected element (ie. this) /// </summary> /// <param name="prop" type="String">CSS Properties to watch sep. by commas</param> /// <param name="func" type="Function"> /// Function called when the value has changed. /// </param> /// <param name="interval" type="Number"> /// Optional interval for browsers that don't support DOMAttrModified or propertychange events. /// Determines the interval used for setInterval calls. /// </param> /// <param name="id" type="String">A unique ID that identifies this watch instance on this element</param> /// <returns type="jQuery" /> if (!interval) interval = 200; if (!id) id = "_watcher"; return this.each(function () { var _t = this; var el$ = $(this); var fnc = function () { __watcher.call(_t, id) }; var itId = null; var data = { id: id, props: props.split(","), func: func, vals: [props.split(",").length], fnc: fnc, origProps: props, interval: interval }; $.each(data.props, function (i) { data.vals[i] = el$.css(data.props[i]); }); el$.data(id, data); hookChange(el$, id, data.fnc); }); function hookChange(el$, id, fnc) { el$.each(function () { var el = $(this); if (typeof (el.get(0).onpropertychange) == "object") el.bind("propertychange." + id, fnc); else if ($.browser.mozilla) el.bind("DOMAttrModified." + id, fnc); else itId = setInterval(fnc, interval); }); } function __watcher(id) { var el$ = $(this); var w = el$.data(id); if (!w) return; var _t = this; if (!w.func) return; // must unbind or else unwanted recursion may occur el$.unwatch(id); var changed = false; var i = 0; for (i; i < w.props.length; i++) { var newVal = el$.css(w.props[i]); if (w.vals[i] != newVal) { w.vals[i] = newVal; changed = true; break; } } if (changed) w.func.call(_t, w, i); // rebind event hookChange(el$, id, w.fnc); } } $.fn.unwatch = function (id) { this.each(function () { var el = $(this); var fnc = el.data(id).fnc; try { if (typeof (this.onpropertychange) == "object") el.unbind("propertychange." + id, fnc); else if ($.browser.mozilla) el.unbind("DOMAttrModified." + id, fnc); else clearInterval(id); } // ignore if element was already unbound catch (e) { } }); return this; } There are basically two jQuery functions - watch and unwatch. jQuery.fn.watch(props,func,interval,id) Starts watching an element for changes in the properties specified. props The CSS properties that are to be watched for changes. If any of the specified properties changes the function specified in the second parameter is fired. func (watchData,index) The function fired in response to a changed property. Receives this as the element changed and object that represents the watched properties and their respective values. The first parameter is passed in this structure:    { id: itId, props: [], func: func, vals: [] }; A second parameter is the index of the changed property so data.props[i] or data.vals[i] gets the property value that has changed. interval The interval for setInterval() for those browsers that don't support property watching in the DOM. In milliseconds. id An optional id that identifies this watcher. Required only if multiple watchers might be hooked up to the same element. The default is _watcher if not specified. jQuery.fn.unwatch(id) Unhooks watching of the element by disconnecting the event handlers. id Optional watcher id that was specified in the call to watch. This value can be omitted to use the default value of _watcher. You can also grab the latest version of the  code for this plug-in as well as the shadow in the full library at: http://www.west-wind.com:8080/svn/jquery/trunk/jQueryControls/Resources/ww.jquery.js watcher has no other dependencies although it lives in this larger library. The shadow plug-in depends on watcher.© Rick Strahl, West Wind Technologies, 2005-2011

    Read the article

  • Any problems usinga GoDaddy SSL certificate on a Cisco ASA firewall?

    - by Richard West
    I need to purchase and install a SSL certificate on my Cisco ASA firewall. This will allow my VPN users to connect to my ASA without receiving the certificate error from the untrusted self assigned SSL certificate that is currently on the ASA. I had good experiences with the SSL certificates that GoDaddy sells. However, I'm concerned about using them. On my web servers I have to also install GoDaddy's "intermediate certificate bundle". On the ASA I do not think that I will be able to preform anything like this. I do not fully understand what the "intermediate certificate bundle" does, but obviously it's important. So my question is can I use a GoDaddy SSL certificate on an ASA without my users getting any type of warning or error about connecting to a site that using an untrusted SSL certificate. I need this to be as simple as possible for my end users and warning messages are always scary :) Thanks!

    Read the article

  • GXT LayoutContainer with scrollbar reports a client height value which includes the area below the s

    - by Pieter Breed
    I have this code which sets up a "main" container into which other modules of the application will go. LayoutContainer c = new LayoutContainer(); c.setScrollMode(Scroll.ALWAYS); parentContainer.add(c, <...>); Then later on, I have the following as an event handler pContainer = c; // pContainer is actually a parameter, but it has c's value pContainer.removeAll(); pContainer.setLayout(new FitLayout()); LayoutContainer wrapperContainer = new LayoutContainer(); wrapperContainer.setLayout(new BorderLayout()); wrapperContainer.setBorders(false); pContainer.add(wrapperContainer); LayoutContainer west = pWestContentContainer; BorderLayoutData westLayoutData = new BorderLayoutData(LayoutRegion.WEST); westLayoutData.setSize(pWidth); westLayoutData.setSplit(true); wrapperContainer.add(west, westLayoutData); LayoutContainer center = new LayoutContainer(); wrapperContainer.add(center, new BorderLayoutData(LayoutRegion.CENTER)); pCallback.withSplitContainer(center); pContainer.layout(); So in effect, the container called 'west' here will be where the module's UI gets displayed. That module UI then does a simple rowlayout with two children. The botton child has RowData(1, 1) so it fills up all the available space. My problem is that the c (parent) container reports a height and width value which includes the value underneath the scrollbars. What I would like is that the scrollbars show all the space excluding their own space. This is a screenshot showing what I mean:

    Read the article

  • what is .motn file?

    - by Wind Chimez
    In a flash based project, i got a few files with extension as ".motn". I am not sure what this file is or more importantly, with what editor/tool i can work on this file. What i guess is this might be a way to create flv movies, out of pictures , vectors and otehr data, but it's just a guess.So, basically i have two doubts: 1. what is a .motn file 2. How /with what tool can i work on a .motn file efficiently. Can anybody help ?

    Read the article

  • C# node graph api to use

    - by wind
    I need display a node graph in c# and find the short possible path(figure 10 of http://msdn.microsoft.com/en-us/library/aa289152(VS.71).aspx). What API can i use to draw out all the node and link? Anyone can advise?

    Read the article

  • File transfer problems through VPN when Cisco IPS is enabled

    - by Richard West
    We have a Cisco ASA 5510 firewall with the IPS module installed. We have a customer that we must connect to via VPN to their network to exchange files via FTP. We use the Cisco VPN client (version 5.0.01.0600) on our local workstations, which are behind the firewall and subject to the IPS. The VPN client is successful in connecting to the remote site. However when we start the FTP file transfer we are able to upload only 150K to 200K of data, then everything stops. A minute later the VPN session is dropped. I think I have isolated this to an IPS issue by temporarily disabling the Service Policy on the ASA for the IPS with the following command: access-list IPS line 1 extended permit ip 0.0.0.0 0.0.0.0 0.0.0.0 0.0.0.0 inactive After this command was issued I then established the VPN to the remote site and was successful in transferring the entire file. While still connected to the VPN and FTP session I issued the command to enable the IPS: access-list IPS line 1 extended permit ip 0.0.0.0 0.0.0.0 0.0.0.0 0.0.0.0 The file transfer was tried again and was once again successful so I closed the FTP session and reopened it, while keeping the same VPN session open. This file transfer was also successful. This told me that nothing with the FTP programs was being filtered or causing the problem. Furthermore, we use FTP to exchange files with many sites everyday without issue. I then disconnected the original VPN session, which was established when the access-list was inactive, and reconnected the VPN session, now with the access-list active. After starting the FTP transfer the file stopped after 150K. To me this seems like the IPS is blocking, or somehow interfering with the initial VPN setup to the remote site. This only started happening last week after the latest IPS signature updates were applied (sig version 407.0). Our previous sig version was 95 days old becuase the system was not auto updating itself. Any ideas on what could be causing this problem?

    Read the article

  • css only menu popout?

    - by aslum
    I'd like to have a logo (say it's square for simplicity) with 4 links that pop up when it is moused over. These would be positioned Above, Below and to the sides of the menu/logo. Is this achievable with only CSS? Any suggestions for how one might go about doing it? Semantically I'd like to order them with in the page something like: <ul><li><a href="Homepage">Logo</a> <ul><li class="north"><a href="north">North</a></li> <li class="west"><a href="west">West</a></li> <li class="east"><a href="east">East</a></li> <li class="south"><a href="south">South</a></li> </ul> </li> </ul> But have them show up on the page like: North West Logo East South

    Read the article

  • "You need to confirm this operation" message when trying to delete a file

    - by Richard West
    I'm trying to delete a few files that I created, and I have full permissions on, on a Windows 2008 system. The files are within a folder that I created so they are not system files of any kind. The message box that pops up when I try to delete the file is titled "Destination Folder Access Denied", and the message is "you need to confirm this operation", with a continue, skip or cancel button. I disabled UAC and rebooted to see if this would make the message go away -- it did not. However, with UAC disabled I am able to click on continue and the files are deleted. With UAC enabled I had to provide elevated credientials before the files would delete. What causes this behaviour and how can I remove it?

    Read the article

< Previous Page | 2 3 4 5 6 7 8 9 10 11 12 13  | Next Page >