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  • Best way to go about sorting 2D sprites in a "RPG Maker" styled RPG

    - by Aaron Stewart
    I am trying to come up with the best way to create overlapping sprites without having any issues. I was thinking of having a SortedDictionary and setting the Entity's key to it's Y position relative to the max bound of the simulation, aka the Z value. I'd update the "Z" value in the update method each frame, if the entity's position has changed at all. For those who don't know what I mean, I want characters who are standing closer in front of another character to be drawn on top, and if they are behind the character, they are drawn behind. I'm leery of using SpriteBatch back to front or front to back, I've been doing some searching and have been under the impression they are a bad idea. and want to know exactly how other people are dealing with their depth sorting. Just ultimately trying to come up with the best method of sorting for good practice before I get too far in to refactor the system effectively.

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  • Yet another blog about IValueConverter

    - by codingbloke
    After my previous blog on a Generic Boolean Value Converter I thought I might as well blog up another IValueConverter implementation that I use. The Generic Boolean Value Converter effectively converters an input which only has two possible values to one of two corresponding objects.  The next logical step would be to create a similar converter that can take an input which has multiple (but finite and discrete) values to one of multiple corresponding objects.  To put it more simply a Generic Enum Value Converter. Now we already have a tool that can help us in this area, the ResourceDictionary.  A simple IValueConverter implementation around it would create a StringToObjectConverter like so:- StringToObjectConverter using System; using System.Windows; using System.Windows.Data; using System.Linq; using System.Windows.Markup; namespace SilverlightApplication1 {     [ContentProperty("Items")]     public class StringToObjectConverter : IValueConverter     {         public ResourceDictionary Items { get; set; }         public string DefaultKey { get; set; }                  public StringToObjectConverter()         {             DefaultKey = "__default__";         }         public virtual object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             if (value != null && Items.Contains(value.ToString()))                 return Items[value.ToString()];             else                 return Items[DefaultKey];         }         public virtual object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             return Items.FirstOrDefault(kvp => value.Equals(kvp.Value)).Key;         }     } } There are some things to note here.  The bulk of managing the relationship between an object instance and the related string key is handled by the Items property being an ResourceDictionary.  Also there is a catch all “__default__” key value which allows for only a subset of the possible input values to mapped to an object with the rest falling through to the default. We can then set one of these up in Xaml:-             <local:StringToObjectConverter x:Key="StatusToBrush">                 <ResourceDictionary>                     <SolidColorBrush Color="Red" x:Key="Overdue" />                     <SolidColorBrush Color="Orange" x:Key="Urgent" />                     <SolidColorBrush Color="Silver" x:Key="__default__" />                 </ResourceDictionary>             </local:StringToObjectConverter> You could well imagine that in the model being bound these key names would actually be members of an enum.  This still works due to the use of ToString in the Convert method.  Hence the only requirement for the incoming object is that it has a ToString implementation which generates a sensible string instead of simply the type name. I can’t imagine right now a scenario where this converter would be used in a TwoWay binding but there is no reason why it can’t.  I prefer to avoid leaving the ConvertBack throwing an exception if that can be be avoided.  Hence it just enumerates the KeyValuePair entries to find a value that matches and returns the key its mapped to. Ah but now my sense of balance is assaulted again.  Whilst StringToObjectConverter is quite happy to accept an enum type via the Convert method it returns a string from the ConvertBack method not the original input enum type that arrived in the Convert.  Now I could address this by complicating the ConvertBack method and examining the targetType parameter etc.  However I prefer to a different approach, deriving a new EnumToObjectConverter class instead. EnumToObjectConverter using System; namespace SilverlightApplication1 {     public class EnumToObjectConverter : StringToObjectConverter     {         public override object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             string key = Enum.GetName(value.GetType(), value);             return base.Convert(key, targetType, parameter, culture);         }         public override object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)         {             string key = (string)base.ConvertBack(value, typeof(String), parameter, culture);             return Enum.Parse(targetType, key, false);         }     } }   This is a more belts and braces solution with specific use of Enum.GetName and Enum.Parse.  Whilst its more explicit in that the a developer has to  choose to use it, it is only really necessary when using TwoWay binding, in OneWay binding the base StringToObjectConverter would serve just as well. The observant might note that there is actually no “Generic” aspect to this solution in the end.  The use of a ResourceDictionary eliminates the need for that.

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  • New release of Microsoft All-In-One Code Framework is available for download - March 2011

    - by Jialiang
    A new release of Microsoft All-In-One Code Framework is available on March 8th. Download address: http://1code.codeplex.com/releases/view/62267#DownloadId=215627 You can download individual code samples or browse code samples grouped by technology in the updated code sample index. If it’s the first time that you hear about Microsoft All-In-One Code Framework, please read this Microsoft News Center article http://www.microsoft.com/presspass/features/2011/jan11/01-13codeframework.mspx, or watch the introduction video on YouTube http://www.youtube.com/watch?v=cO5Li3APU58, or read the introduction on our homepage http://1code.codeplex.com/. -------------- New Silverlight code samples CSSLTreeViewCRUDDragDrop Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215808 The code sample was created by Amit Dey. It demonstrates a custom TreeView with added functionalities of CRUD (Create, Read, Update, Delete) and drag-and-drop operations. Silverlight TreeView control with CRUD and drag & drop is a frequently asked programming question in Silverlight  forums. Many customers also requested this code sample in our code sample request service. We hope that this sample can reduce developers' efforts in handling this typical programming scenario. The following blog article introduces the sample in detail: http://blogs.msdn.com/b/codefx/archive/2011/02/15/silverlight-treeview-control-with-crud-and-drag-amp-drop.aspx. CSSL4FileDragDrop and VBSL4FileDragDrop Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215809 http://1code.codeplex.com/releases/view/62253#DownloadId=215810 The code sample demonstrates the new drag&drop feature of Silverlight 4 to implement dragging picures from the local file system to a Silverlight application.   Sometimes we want to change SiteMapPath control's titles and paths according to Query String values. And sometimes we want to create the SiteMapPath dynamically. This code sample shows how to achieve these goals by handling SiteMap.SiteMapResolve event. CSASPNETEncryptAndDecryptConfiguration, VBASPNETEncryptAndDecryptConfiguration Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215027 http://1code.codeplex.com/releases/view/62253#DownloadId=215106 In this sample, we encrypt and decrypt some sensitive information in the config file of a web application by using the RSA asymmetric encryption. This project contains two snippets. The first one demonstrates how to use RSACryptoServiceProvider to generate public key and the corresponding private key and then encrypt/decrypt string value on page. The second part shows how to use RSA configuration provider to encrypt and decrypt configuration section in web.config of web application. connectionStrings section in plain text: Encrypted connectionString:  Note that if you store sensitive data in any of the following configuration sections, we cannot encrypt it by using a protected configuration provider <processModel> <runtime> <mscorlib> <startup> <system.runtime.remoting> <configProtectedData> <satelliteassemblies> <cryptographySettings> <cryptoNameMapping> CSASPNETFileUploadStatus Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215028 I believe ASP.NET programmers will like this sample, because in many cases we need customers know the current status of the uploading files, including the upload speed and completion percentage and so on. Under normal circumstances, we need to use COM components to accomplish this function, such as Flash, Silverlight, etc. The uploading data can be retrieved in two places, the client-side and the server-side. For the client, for the safety factors, the file upload status information cannot be got from JavaScript or server-side code, so we need COM component, like Flash and Silverlight to accomplish this, I do not like this approach because the customer need to install these components, but also we need to learn another programming framework. For the server side, we can get the information through coding, but the key question is how to tell the client results. In this case, We will combine custom HTTPModule and AJAX technology to illustrate how to analyze the HTTP protocol, how to break the file request packets, how to customize the location of the server-side file caching, how to return the file uploading status back to the client and so on . CSASPNETHighlightCodeInPage, VBASPNETHighlightCodeInPage Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215029 http://1code.codeplex.com/releases/view/62253#DownloadId=215108 This sample imitates a system that needs display the highlighted code in an ASP.NET page . As a matter of fact, sometimes we input code like C# or HTML in a web page and we need these codes to be highlighted for a better reading experience. It is convenient for us to keep the code in mind if it is highlighted. So in this case, the sample shows how to highlight the code in an ASP.NET page. It is not difficult to highlight the code in a web page by using String.Replace method directly. This  method can return a new string in which all occurrences of a specified string in the current instance are replaced with another specified string. However, it may not be a good idea, because it's not extremely fast, in fact, it's pretty slow. In addition, it is hard to highlight multiple keywords by using String.Replace method directly. Sometimes we need to copy source code from visual studio to a web page, for readability purpose, highlight the code is important while set the different types of keywords to different colors in a web page by using String.Replace method directly is not available. To handle this issue, we need to use a hashtable variable to store the different languages of code and their related regular expressions with matching options. Furthermore, define the css styles which used to highlight the code in a web page. The sample project can auto add the style object to the matching string of code. A step-by-step guide illustrating how to highlight the code in an ASP.NET page: 1. the HighlightCodePage.aspx page Choose a type of language in the dropdownlist control and paste the code in the textbox control, then click the HighLight button. 2.  Display the highlighted code in an ASP.NET page After user clicks the HighLight button, the highlighted code will be displayed at right side of the page.        CSASPNETPreventMultipleWindows Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215032 This sample demonstrates a step-by-step guide illustrating how to detect and prevent multiple windows or tab usage in Web Applications. The sample imitates a system that need to prevent multiple windows or tabs to solve some problems like sharing sessions, protect duplicated login, data concurrency, etc. In fact, there are many methods achieving this goal. Here we give a solution of use JavaScript, Sample shows how to use window.name property check the correct links and throw other requests to invalid pages. This code-sample use two user controls to make a distinction between base page and target page, user only need drag different controls to appropriate web form pages. so user need not write repetitive code in every page, it will make coding work lightly and convenient for modify your code.  JSVirtualKeyboard Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215093 This article describes an All-In-One framework sample that demonstrates a step-by-step guide illustrating how to build a virtual keyboard in your HTML page. Sometimes we may need to offer a virtual keyboard to let users input something without their real keyboards. This scenario often occurs when users will enter their password to get access to our sites and we want to protect the password from some kinds of back-door software, a Key-logger for example, and we will find a virtual keyboard on the page will be a good choice here. To create a virtual keyboard, we firstly need to add some buttons to the page. And when users click on a certain button, the JavaScript function handling the onclick event will input an appropriated character to the textbox. That is the simple logic of this feature. However, if we indeed want a virtual keyboard to substitute for the real keyboard completely, we will need more advanced logic to handle keys like Caps-Lock and Shift etc. That will be a complex work to achieve. CSASPNETDataListImageGallery Download: http://1code.codeplex.com/releases/view/62261#DownloadId=215267 This code sample demonstrates how to create an Image Gallery application by using the DataList control in ASP.NET. You may find the Image Gallery is widely used in many social networking sites, personal websites and E-Business websites. For example, you may use the Image Gallery to show a library of personal uploaded images on a personal website. Slideshow is also a popular tool to display images on websites. This code sample demonstrates how to use the DataList and ImageButton controls in ASP.NET to create an Image Gallery with image navigation. You can click on a thumbnail image in the Datalist control to display a larger version of the image on the page. This sample code reads the image paths from a certain directory into a FileInfo array. Then, the FileInfo array is used to populate a custom DataTable object which is bound to the Datalist control. This code sample also implements a custom paging system that allows five images to be displayed horizontally on one page. The following link buttons are used to implement a custom paging system:   •     First •     Previous •     Next •     Last Note We recommend that you use this method to load no more than five images at a time. You can also set the SelectedIndex property for the DataList control to limit the number of the thumbnail images that can be selected. To indicate which image is selected, you can set the SelectedStyle property for the DataList control. VBASPNETSearchEngine Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215112 This sample shows how to implement a simple search engine in an ASP.NET web site. It uses LIKE condition in SQL statement to search database. Then it highlights keywords in search result by using Regular Expression and JavaScript. New Windows General code samples CSCheckEXEType, VBCheckEXEType Downloads: http://1code.codeplex.com/releases/view/62253#DownloadId=215045 http://1code.codeplex.com/releases/view/62253#DownloadId=215120 The sample demonstrates how to check an executable file type.  For a given executable file, we can get 1 whether it is a console application 2 whether it is a .Net application 3 whether it is a 32bit native application. 4 The full display name of a .NET application, e.g. System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL New Internet Explorer code samples CSIEExplorerBar, VBIEExplorerBar Downloads: http://1code.codeplex.com/releases/view/62253#DownloadId=215060 http://1code.codeplex.com/releases/view/62253#DownloadId=215133 The sample demonstrates how to create and deploy an IE Explorer Bar which could list all the images in a web page. CSBrowserHelperObject, VBBrowserHelperObject Downloads: http://1code.codeplex.com/releases/view/62253#DownloadId=215044 http://1code.codeplex.com/releases/view/62253#DownloadId=215119 The sample demonstrates how to create and deploy a Browser Helper Object,  and the BHO in this sample is used to disable the context menu in IE. New Windows Workflow Foundation code samples CSWF4ActivitiesCorrelation Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215085 Consider that there are two such workflow instances:       start                                   start          |                                           | Receive activity      Receive activity         |                                           | Receive2 activity      Receive2 activity         |                                           | A WCF request comes to call the second Receive2 activity. Which one should take care of the request? The answer is Correlation. This sample will show you how to correlate two workflow service to work together. -------------- New ASP.NET code samples CSASPNETBreadcrumbWithQueryString Download: http://1code.codeplex.com/releases/view/62253#DownloadId=215022

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  • AWS .NET SDK v2: the message-pump pattern

    - by Elton Stoneman
    Originally posted on: http://geekswithblogs.net/EltonStoneman/archive/2013/10/11/aws-.net-sdk-v2--the-message-pump-pattern.aspxVersion 2 of the AWS SDK for .NET has had a few pre-release iterations on NuGet and is stable, if a bit lacking in step-by-step guides. There’s at least one big reason to try it out: the SQS queue client now supports asynchronous reads, so you don’t need a clumsy polling mechanism to retrieve messages. The new approach  is easy to use, and lets you work with AWS queues in a similar way to the message-pump pattern used in the latest Azure SDK for Service Bus queues and topics. I’ve posted a simple wrapper class for subscribing to an SQS hub on gist here: A wrapper for the SQS client in the AWS SDK for.NET v2, which uses the message-pump pattern. Here’s the core functionality in the subscribe method: private async void Subscribe() { if (_isListening) { var request = new ReceiveMessageRequest { MaxNumberOfMessages = 10 }; request.QueueUrl = QueueUrl; var result = await _sqsClient.ReceiveMessageAsync(request, _cancellationTokenSource.Token); if (result.Messages.Count > 0) { foreach (var message in result.Messages) { if (_receiveAction != null && message != null) { _receiveAction(message.Body); DeleteMessage(message.ReceiptHandle); } } } } if (_isListening) { Subscribe(); } } which you call with something like this: client.Subscribe(x=>Log.Debug(x.Body)); The async SDK call returns when there is something in the queue, and will run your receive action for every message it gets in the batch (defaults to the maximum size of 10 messages per call). The listener will sit there awaiting messages until you stop it with: client.Unsubscribe(); Internally it has a cancellation token which it sets when you call unsubscribe, which cancels any in-flight call to SQS and stops the pump. The wrapper will also create the queue if it doesn’t exist at runtime. The Ensure() method gets called in the constructor so when you first use the client for a queue (sending or subscribing), it will set itself up: if (!Exists()) { var request = new CreateQueueRequest(); request.QueueName = QueueName; var response = _sqsClient.CreateQueue(request); QueueUrl = response.QueueUrl; } The Exists() check has to do make a call to ListQueues on the SNS client, as it doesn’t provide its own method to check if a queue exists. That call also populates the Amazon Resource Name, the unique identifier for this queue, which will be useful later. To use the wrapper, just instantiate and go: var queueClient = new QueueClient(“ProcessWorkflow”); queueClient.Subscribe(x=>Log.Debug(x.Body)); var message = {}; //etc. queueClient.Send(message);

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  • DB Documentation Tool

    - by Hisham El-bereky
     Recently I have uploaded new project to codeplex site, DbDocument or DbDoc project is a helper tool used side by side with MS SQL server management studio tool, you can design your DB Tables in visualized way through Diagrams and then use “DbDoc” tool to generate design document in MS Word format, the generated file can be used in design review process or as history reference, the tool facilitate and reduce the time of writing DB structure documentthe current version is not so sophisticated which is intend to generate word document in table format with all tables in DB illustrating its structure and constraints, but for now it seems to be good.   For more details check DbDoc document or go immediately to DbDoc home page http://dbdocument.codeplex.com/

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  • How to Transfer All Your Information to a New PS3: Video Tutorial

    - by Justin Garrison
    We have already shown you the steps needed to transfer all your information to a new PS3, but for those of you who would like to see the whole process from start to finish we put together this video. If you need any clarification on the steps involved don’t forget to check out the original post with more details. How to Transfer All Your Information to a New PS3 Latest Features How-To Geek ETC How to Get Amazing Color from Photos in Photoshop, GIMP, and Paint.NET Learn To Adjust Contrast Like a Pro in Photoshop, GIMP, and Paint.NET Have You Ever Wondered How Your Operating System Got Its Name? Should You Delete Windows 7 Service Pack Backup Files to Save Space? What Can Super Mario Teach Us About Graphics Technology? Windows 7 Service Pack 1 is Released: But Should You Install It? Get the MakeUseOf eBook Guide to Hacker Proofing Your PC Sync Your Windows Computer with Your Ubuntu One Account [Desktop Client] Awesome 10 Meter Curved Touchscreen at the University of Groningen [Video] TV Antenna Helper Makes HDTV Antenna Calibration a Snap Turn a Green Laser into a Microscope Projector [Science] The Open Road Awaits [Wallpaper]

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  • Optimizing graphics for an iOS flash game

    - by 1GR3
    A friend of mine and myself are working on a flash developed iOS (and later Android) puzzle board game. He's a developer and I'm a designer/developer so (no surprise) we have different points of view. His method: make small tiles (100x100px) in Photoshop join them into the board and then in flash apply effects to the board to avoid repetition (80's not in the good way). My method: precompose the whole board (960x640px+bleed) in Photoshop and than mask active and inactive areas in flash. What do you think?

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  • Microsoft Introduces WebMatrix

    - by Rick Strahl
    originally published in CoDe Magazine Editorial Microsoft recently released the first CTP of a new development environment called WebMatrix, which along with some of its supporting technologies are squarely aimed at making the Microsoft Web Platform more approachable for first-time developers and hobbyists. But in the process, it also provides some updated technologies that can make life easier for existing .NET developers. Let’s face it: ASP.NET development isn’t exactly trivial unless you already have a fair bit of familiarity with sophisticated development practices. Stick a non-developer in front of Visual Studio .NET or even the Visual Web Developer Express edition and it’s not likely that the person in front of the screen will be very productive or feel inspired. Yet other technologies like PHP and even classic ASP did provide the ability for non-developers and hobbyists to become reasonably proficient in creating basic web content quickly and efficiently. WebMatrix appears to be Microsoft’s attempt to bring back some of that simplicity with a number of technologies and tools. The key is to provide a friendly and fully self-contained development environment that provides all the tools needed to build an application in one place, as well as tools that allow publishing of content and databases easily to the web server. WebMatrix is made up of several components and technologies: IIS Developer Express IIS Developer Express is a new, self-contained development web server that is fully compatible with IIS 7.5 and based on the same codebase that IIS 7.5 uses. This new development server replaces the much less compatible Cassini web server that’s been used in Visual Studio and the Express editions. IIS Express addresses a few shortcomings of the Cassini server such as the inability to serve custom ISAPI extensions (i.e., things like PHP or ASP classic for example), as well as not supporting advanced authentication. IIS Developer Express provides most of the IIS 7.5 feature set providing much better compatibility between development and live deployment scenarios. SQL Server Compact 4.0 Database access is a key component for most web-driven applications, but on the Microsoft stack this has mostly meant you have to use SQL Server or SQL Server Express. SQL Server Compact is not new-it’s been around for a few years, but it’s been severely hobbled in the past by terrible tool support and the inability to support more than a single connection in Microsoft’s attempt to avoid losing SQL Server licensing. The new release of SQL Server Compact 4.0 supports multiple connections and you can run it in ASP.NET web applications simply by installing an assembly into the bin folder of the web application. In effect, you don’t have to install a special system configuration to run SQL Compact as it is a drop-in database engine: Copy the small assembly into your BIN folder (or from the GAC if installed fully), create a connection string against a local file-based database file, and then start firing SQL requests. Additionally WebMatrix includes nice tools to edit the database tables and files, along with tools to easily upsize (and hopefully downsize in the future) to full SQL Server. This is a big win, pending compatibility and performance limits. In my simple testing the data engine performed well enough for small data sets. This is not only useful for web applications, but also for desktop applications for which a fully installed SQL engine like SQL Server would be overkill. Having a local data store in those applications that can potentially be accessed by multiple users is a welcome feature. ASP.NET Razor View Engine What? Yet another native ASP.NET view engine? We already have Web Forms and various different flavors of using that view engine with Web Forms and MVC. Do we really need another? Microsoft thinks so, and Razor is an implementation of a lightweight, script-only view engine. Unlike the Web Forms view engine, Razor works only with inline code, snippets, and markup; therefore, it is more in line with current thinking of what a view engine should represent. There’s no support for a “page model” or any of the other Web Forms features of the full-page framework, but just a lightweight scripting engine that works with plain markup plus embedded expressions and code. The markup syntax for Razor is geared for minimal typing, plus some progressive detection of where a script block/expression starts and ends. This results in a much leaner syntax than the typical ASP.NET Web Forms alligator (<% %>) tags. Razor uses the @ sign plus standard C# (or Visual Basic) block syntax to delineate code snippets and expressions. Here’s a very simple example of what Razor markup looks like along with some comment annotations: <!DOCTYPE html> <html>     <head>         <title></title>     </head>     <body>     <h1>Razor Test</h1>          <!-- simple expressions -->     @DateTime.Now     <hr />     <!-- method expressions -->     @DateTime.Now.ToString("T")          <!-- code blocks -->     @{         List<string> names = new List<string>();         names.Add("Rick");         names.Add("Markus");         names.Add("Claudio");         names.Add("Kevin");     }          <!-- structured block statements -->     <ul>     @foreach(string name in names){             <li>@name</li>     }     </ul>           <!-- Conditional code -->        @if(true) {                        <!-- Literal Text embedding in code -->        <text>         true        </text>;    }    else    {        <!-- Literal Text embedding in code -->       <text>       false       </text>;    }    </body> </html> Like the Web Forms view engine, Razor parses pages into code, and then executes that run-time compiled code. Effectively a “page” becomes a code file with markup becoming literal text written into the Response stream, code snippets becoming raw code, and expressions being written out with Response.Write(). The code generated from Razor doesn’t look much different from similar Web Forms code that only uses script tags; so although the syntax may look different, the operational model is fairly similar to the Web Forms engine minus the overhead of the large Page object model. However, there are differences: -Razor pages are based on a new base class, Microsoft.WebPages.WebPage, which is hosted in the Microsoft.WebPages assembly that houses all the Razor engine parsing and processing logic. Browsing through the assembly (in the generated ASP.NET Temporary Files folder or GAC) will give you a good idea of the functionality that Razor provides. If you look closely, a lot of the feature set matches ASP.NET MVC’s view implementation as well as many of the helper classes found in MVC. It’s not hard to guess the motivation for this sort of view engine: For beginning developers the simple markup syntax is easier to work with, although you obviously still need to have some understanding of the .NET Framework in order to create dynamic content. The syntax is easier to read and grok and much shorter to type than ASP.NET alligator tags (<% %>) and also easier to understand aesthetically what’s happening in the markup code. Razor also is a better fit for Microsoft’s vision of ASP.NET MVC: It’s a new view engine without the baggage of Web Forms attached to it. The engine is more lightweight since it doesn’t carry all the features and object model of Web Forms with it and it can be instantiated directly outside of the HTTP environment, which has been rather tricky to do for the Web Forms view engine. Having a standalone script parser is a huge win for other applications as well – it makes it much easier to create script or meta driven output generators for many types of applications from code/screen generators, to simple form letters to data merging applications with user customizability. For me personally this is very useful side effect and who knows maybe Microsoft will actually standardize they’re scripting engines (die T4 die!) on this engine. Razor also better fits the “view-based” approach where the view is supposed to be mostly a visual representation that doesn’t hold much, if any, code. While you can still use code, the code you do write has to be self-contained. Overall I wouldn’t be surprised if Razor will become the new standard view engine for MVC in the future – and in fact there have been announcements recently that Razor will become the default script engine in ASP.NET MVC 3.0. Razor can also be used in existing Web Forms and MVC applications, although that’s not working currently unless you manually configure the script mappings and add the appropriate assemblies. It’s possible to do it, but it’s probably better to wait until Microsoft releases official support for Razor scripts in Visual Studio. Once that happens, you can simply drop .cshtml and .vbhtml pages into an existing ASP.NET project and they will work side by side with classic ASP.NET pages. WebMatrix Development Environment To tie all of these three technologies together, Microsoft is shipping WebMatrix with an integrated development environment. An integrated gallery manager makes it easy to download and load existing projects, and then extend them with custom functionality. It seems to be a prominent goal to provide community-oriented content that can act as a starting point, be it via a custom templates or a complete standard application. The IDE includes a project manager that works with a single project and provides an integrated IDE/editor for editing the .cshtml and .vbhtml pages. A run button allows you to quickly run pages in the project manager in a variety of browsers. There’s no debugging support for code at this time. Note that Razor pages don’t require explicit compilation, so making a change, saving, and then refreshing your page in the browser is all that’s needed to see changes while testing an application locally. It’s essentially using the auto-compiling Web Project that was introduced with .NET 2.0. All code is compiled during run time into dynamically created assemblies in the ASP.NET temp folder. WebMatrix also has PHP Editing support with syntax highlighting. You can load various PHP-based applications from the WebMatrix Web Gallery directly into the IDE. Most of the Web Gallery applications are ready to install and run without further configuration, with Wizards taking you through installation of tools, dependencies, and configuration of the database as needed. WebMatrix leverages the Web Platform installer to pull the pieces down from websites in a tight integration of tools that worked nicely for the four or five applications I tried this out on. Click a couple of check boxes and fill in a few simple configuration options and you end up with a running application that’s ready to be customized. Nice! You can easily deploy completed applications via WebDeploy (to an IIS server) or FTP directly from within the development environment. The deploy tool also can handle automatically uploading and installing the database and all related assemblies required, making deployment a simple one-click install step. Simplified Database Access The IDE contains a database editor that can edit SQL Compact and SQL Server databases. There is also a Database helper class that facilitates database access by providing easy-to-use, high-level query execution and iteration methods: @{       var db = Database.OpenFile("FirstApp.sdf");     string sql = "select * from customers where Id > @0"; } <ul> @foreach(var row in db.Query(sql,1)){         <li>@row.FirstName @row.LastName</li> } </ul> The query function takes a SQL statement plus any number of positional (@0,@1 etc.) SQL parameters by simple values. The result is returned as a collection of rows which in turn have a row object with dynamic properties for each of the columns giving easy (though untyped) access to each of the fields. Likewise Execute and ExecuteNonQuery allow execution of more complex queries using similar parameter passing schemes. Note these queries use string-based queries rather than LINQ or Entity Framework’s strongly typed LINQ queries. While this may seem like a step back, it’s also in line with the expectations of non .NET script developers who are quite used to writing and using SQL strings in code rather than using OR/M frameworks. The only question is why was something not included from the beginning in .NET and Microsoft made developers build custom implementations of these basic building blocks. The implementation looks a lot like a DataTable-style data access mechanism, but to be fair, this is a common approach in scripting languages. This type of syntax that uses simple, static, data object methods to perform simple data tasks with one line of code are common in scripting languages and are a good match for folks working in PHP/Python, etc. Seems like Microsoft has taken great advantage of .NET 4.0’s dynamic typing to provide this sort of interface for row iteration where each row has properties for each field. FWIW, all the examples demonstrate using local SQL Compact files - I was unable to get a SQL Server connection string to work with the Database class (the connection string wasn’t accepted). However, since the code in the page is still plain old .NET, you can easily use standard ADO.NET code or even LINQ or Entity Framework models that are created outside of WebMatrix in separate assemblies as required. The good the bad the obnoxious - It’s still .NET The beauty (or curse depending on how you look at it :)) of Razor and the compilation model is that, behind it all, it’s still .NET. Although the syntax may look foreign, it’s still all .NET behind the scenes. You can easily access existing tools, helpers, and utilities simply by adding them to the project as references or to the bin folder. Razor automatically recognizes any assembly reference from assemblies in the bin folder. In the default configuration, Microsoft provides a host of helper functions in a Microsoft.WebPages assembly (check it out in the ASP.NET temp folder for your application), which includes a host of HTML Helpers. If you’ve used ASP.NET MVC before, a lot of the helpers should look familiar. Documentation at the moment is sketchy-there’s a very rough API reference you can check out here: http://www.asp.net/webmatrix/tutorials/asp-net-web-pages-api-reference Who needs WebMatrix? Uhm… good Question Clearly Microsoft is trying hard to create an environment with WebMatrix that is easy to use for newbie developers. The goal seems to be simplicity in providing a minimal development environment and an easy-to-use script engine/language that makes it easy to get started with. There’s also some focus on community features that can be used as starting points, such as Web Gallery applications and templates. The community features in particular are very nice and something that would be nice to eventually see in Visual Studio as well. The question is whether this is too little too late. Developers who have been clamoring for a simpler development environment on the .NET stack have mostly left for other simpler platforms like PHP or Python which are catering to the down and dirty developer. Microsoft will be hard pressed to win those folks-and other hardcore PHP developers-back. Regardless of how much you dress up a script engine fronted by the .NET Framework, it’s still the .NET Framework and all the complexity that drives it. While .NET is a fine solution in its breadth and features once you get a basic handle on the core features, the bar of entry to being productive with the .NET Framework is still pretty high. The MVC style helpers Microsoft provides are a good step in the right direction, but I suspect it’s not enough to shield new developers from having to delve much deeper into the Framework to get even basic applications built. Razor and its helpers is trying to make .NET more accessible but the reality is that in order to do useful stuff that goes beyond the handful of simple helpers you still are going to have to write some C# or VB or other .NET code. If the target is a hobby/amateur/non-programmer the learning curve isn’t made any easier by WebMatrix it’s just been shifted a tad bit further along in your development endeavor when you run out of canned components that are supplied either by Microsoft or the community. The database helpers are interesting and actually I’ve heard a lot of discussion from various developers who’ve been resisting .NET for a really long time perking up at the prospect of easier data access in .NET than the ridiculous amount of code it takes to do even simple data access with raw ADO.NET. It seems sad that such a simple concept and implementation should trigger this sort of response (especially since it’s practically trivial to create helpers like these or pick them up from countless libraries available), but there it is. It also shows that there are plenty of developers out there who are more interested in ‘getting stuff done’ easily than necessarily following the latest and greatest practices which are overkill for many development scenarios. Sometimes it seems that all of .NET is focused on the big life changing issues of development, rather than the bread and butter scenarios that many developers are interested in to get their work accomplished. And that in the end may be WebMatrix’s main raison d'être: To bring some focus back at Microsoft that simpler and more high level solutions are actually needed to appeal to the non-high end developers as well as providing the necessary tools for the high end developers who want to follow the latest and greatest trends. The current version of WebMatrix hits many sweet spots, but it also feels like it has a long way to go before it really can be a tool that a beginning developer or an accomplished developer can feel comfortable with. Although there are some really good ideas in the environment (like the gallery for downloading apps and components) which would be a great addition for Visual Studio as well, the rest of the development environment just feels like crippleware with required functionality missing especially debugging and Intellisense, but also general editor support. It’s not clear whether these are because the product is still in an early alpha release or whether it’s simply designed that way to be a really limited development environment. While simple can be good, nobody wants to feel left out when it comes to necessary tool support and WebMatrix just has that left out feeling to it. If anything WebMatrix’s technology pieces (which are really independent of the WebMatrix product) are what are interesting to developers in general. The compact IIS implementation is a nice improvement for development scenarios and SQL Compact 4.0 seems to address a lot of concerns that people have had and have complained about for some time with previous SQL Compact implementations. By far the most interesting and useful technology though seems to be the Razor view engine for its light weight implementation and it’s decoupling from the ASP.NET/HTTP pipeline to provide a standalone scripting/view engine that is pluggable. The first winner of this is going to be ASP.NET MVC which can now have a cleaner view model that isn’t inconsistent due to the baggage of non-implemented WebForms features that don’t work in MVC. But I expect that Razor will end up in many other applications as a scripting and code generation engine eventually. Visual Studio integration for Razor is currently missing, but is promised for a later release. The ASP.NET MVC team has already mentioned that Razor will eventually become the default MVC view engine, which will guarantee continued growth and development of this tool along those lines. And the Razor engine and support tools actually inherit many of the features that MVC pioneered, so there’s some synergy flowing both ways between Razor and MVC. As an existing ASP.NET developer who’s already familiar with Visual Studio and ASP.NET development, the WebMatrix IDE doesn’t give you anything that you want. The tools provided are minimal and provide nothing that you can’t get in Visual Studio today, except the minimal Razor syntax highlighting, so there’s little need to take a step back. With Visual Studio integration coming later there’s little reason to look at WebMatrix for tooling. It’s good to see that Microsoft is giving some thought about the ease of use of .NET as a platform For so many years, we’ve been piling on more and more new features without trying to take a step back and see how complicated the development/configuration/deployment process has become. Sometimes it’s good to take a step - or several steps - back and take another look and realize just how far we’ve come. WebMatrix is one of those reminders and one that likely will result in some positive changes on the platform as a whole. © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET   IIS7  

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  • SQL SERVER – Puzzle Involving NULL – Resolve – Error – Operand data type void type is invalid for sum operator

    - by pinaldave
    Today is Monday let us start this week with interesting puzzle. Yesterday I had also posted quick question here: SQL SERVER – T-SQL Scripts to Find Maximum between Two Numbers Run following code: SELECT SUM(data) FROM (SELECT NULL AS DATA) t It will throw following error. Msg 8117, Level 16, State 1, Line 1 Operand data type void type is invalid for sum operator. I can easily fix if I use ISNULL Function as displayed following. SELECT SUM(data) FROM (SELECT ISNULL(NULL,0) AS DATA) t Above script will not throw an error. However, there is one more method how this can be fixed. Can you come up with another method which will not generate error? Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • Which is better : Storing/retrieving images on/from SQL server or in a directory on server

    - by Pankaj Upadhyay
    I am working on a project in Asp.net MVC and need to work with images. There is an SQL database with a Product table. Every product in the table will have it's own image. I have two ways to do this : 1) Save the image in a web directory and store the URL on database. 2) Store the image in SQL itself in binary format and then retrieve it. Which is a better approach ? Mind you, I have no idea how second method works :-P . I will only learn this if there are merits to the second method

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  • Matrix rotation of a rectangle to "face" a given point in 2d

    - by justin.m.chase
    Suppose you have a rectangle centered at point (0, 0) and now I want to rotate it such that it is facing the point (100, 100), how would I do this purely with matrix math? To give some more specifics I am using javascript and canvas and I may have something like this: var position = {x : 0, y: 0 }; var destination = { x : 100, y: 100 }; var transform = Matrix.identity(); this.update = function(state) { // update transform to rotate to face destination }; this.draw = function(ctx) { ctx.save(); ctx.transform(transform); // a helper that just calls setTransform() ctx.beginPath(); ctx.rect(-5, -5, 10, 10); ctx.fillStyle = 'Blue'; ctx.fill(); ctx.lineWidth = 2; ctx.stroke(); ctx.restore(); } Feel free to assume any matrix function you need is available.

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  • Dynamic Tab Implementation in ADF

    - by Vijay Mohan
    Well, this can be a common usecase across apps to open tabs dynamically at runtime based on the request.Well, in order to achieve this you can have a parent container, lets say a panelTab component.Inside panelTab , u can have a showDetailItem inside an af:foreach or an af:iterator binded to a bean static list which will have as many show detail items as you wish to be shown.something like this.private static List = { new showDetailItem("1"),new ShowDetailItem("2") ...};now in the backing bean you can have a method that takes care of rendering and disclosing an specific tab based on the index.public void openMyTab(){List<MyItems> list = refToParentContainer.getChildren();int indexOfTabToBeOpened = //Write a method that will compute the tab index of the next //tab.list.get(index).setRendered(true);list.get(index).setDisclosed(true);similarly you can set other properties too.}Else, instead of having af:foreach/iterator iterating through the SD items , you can go for static SDs in the page with render property set to false and then you can follow the same approach to render/disclose it at runtime.

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  • Building Publishing Pages in Code

    - by David Jacobus
    Originally posted on: http://geekswithblogs.net/djacobus/archive/2013/10/27/154478.aspxOne of the Mantras we developers try to follow: Ensure that the solution package we deliver to the client is complete.  We build Web Parts, Master Pages, Images, CSS files and other artifacts that we push to the client with a WSP (Solution Package) And then we have them finish the solution by building their site pages by adding the web parts to the site pages.       I am a proponent that we,  the developers,  should minimize this time consuming work and build these site pages in code.  I found a few blogs and some MSDN documentation but not really a complete solution that has all these artifacts working in one solution.   What I am will discuss and provide a solution for is a package that has: 1.  Master Page 2.  Page Layout 3.  Page Web Parts 4.  Site Pages   Most all done in code without the development team or the developers having to finish up the site building process spending a few hours or days completing the site!  I am not implying that in Development we do this. In fact,  we build these pages incrementally testing our web parts, etc. I am saying that the final action in our solution is that we take all these artifacts and add them to the site pages in code, the client then only needs to activate a few features and VIOLA their site appears!.  I had a project that had me build 8 pages like this as part of the solution.   In this blog post, I am taking a master page solution that I have called DJGreenMaster.  On My Office 365 Development Site it looks like this:     It is a generic master page for a SharePoint 2010 site Along with a three column layout.  Centered with a footer that uses a SharePoint List and Web Part for the footer links.  I use this master page a lot in my site development!  Easy to change the color and site logo with a little CSS.   I am going to add a few web parts for discussion purposes and then add these web parts to a site page in code.    Lets look at the solution package for DJ Green Master as that will be the basis project for building the site pages:   What you are seeing  is a complete solution to add a Master Page to a site collection which contains: 1.  Master Page Module which contains the Master Page and Page Layout 2.  The Footer Module to add the Footer Web Part 3.  Miscellaneous modules to add images, JQuery, CSS and subsite page 4.  3 features and two feature event receivers: a.  DJGreenCSS, used to add the master page CSS file to Style Sheet Library and an Event Receiver to check it in. b.  DJGreenMaster used to add the Master Page and Page Layout.  In an Event Receiver change the master page to DJGreenMaster , create the footer list and check the files in. c.  DJGreenMasterWebParts add the Footer Web Part to the site collection. I won’t go over the code for this as I will give it to you at the end of this blog post. I have discussed creating a list in code in a previous post.  So what we have is the basis to begin what is germane to this discussion.  I have the first two requirements completed.  I need now to add page web parts and the build the pages in code.  For the page web parts, I will use one downloaded from Codeplex which does not use a SharePoint custom list for simplicity:   Weather Web Part and another downloaded from MSDN which is a SharePoint Custom Calendar Web Part, I had to add some functionality to make the events color coded to exceed the built-in 10 overlays using JQuery!    Here is the solution with the added projects:     Here is a screen shot of the Weather Web Part Deployed:   Here is a screen shot of the Site Calendar with JQuery:     Okay, Now we get to the final item:  To create Publishing pages.   We need to add a feature receiver to the DJGreenMaster project I will name it DJSitePages and also add a Event Receiver:       We will build the page at the site collection level and all of the code necessary will be contained in the event receiver.   Added a reference to the Microsoft.SharePoint.Publishing.dll contained in the ISAPI folder of the 14 Hive.   First we will add some static methods from which we will call  in our Event Receiver:   1: private static void checkOut(string pagename, PublishingPage p) 2: { 3: if (p.Name.Equals(pagename, StringComparison.InvariantCultureIgnoreCase)) 4: { 5: 6: if (p.ListItem.File.CheckOutType == SPFile.SPCheckOutType.None) 7: { 8: p.CheckOut(); 9: } 10:   11: if (p.ListItem.File.CheckOutType == SPFile.SPCheckOutType.Online) 12: { 13: p.CheckIn("initial"); 14: p.CheckOut(); 15: } 16: } 17: } 18: private static void checkin(PublishingPage p,PublishingWeb pw) 19: { 20: SPFile publishFile = p.ListItem.File; 21:   22: if (publishFile.CheckOutType != SPFile.SPCheckOutType.None) 23: { 24:   25: publishFile.CheckIn( 26:   27: "CheckedIn"); 28:   29: publishFile.Publish( 30:   31: "published"); 32: } 33: // In case of content approval, approve the file need to add 34: //pulishing site 35: if (pw.PagesList.EnableModeration) 36: { 37: publishFile.Approve("Initial"); 38: } 39: publishFile.Update(); 40: }   In a Publishing Site, CheckIn and CheckOut  are required when dealing with pages in a publishing site.  Okay lets look at the Feature Activated Event Receiver: 1: public override void FeatureActivated(SPFeatureReceiverProperties properties) 2: { 3:   4:   5:   6: object oParent = properties.Feature.Parent; 7:   8:   9:   10: if (properties.Feature.Parent is SPWeb) 11: { 12:   13: currentWeb = (SPWeb)oParent; 14:   15: currentSite = currentWeb.Site; 16:   17: } 18:   19: else 20: { 21:   22: currentSite = (SPSite)oParent; 23:   24: currentWeb = currentSite.RootWeb; 25:   26: } 27: 28:   29: //create the publishing pages 30: CreatePublishingPage(currentWeb, "Home.aspx", "ThreeColumnLayout.aspx","Home"); 31: //CreatePublishingPage(currentWeb, "Dummy.aspx", "ThreeColumnLayout.aspx","Dummy"); 32: }     Basically we are calling the method Create Publishing Page with parameters:  Current Web, Name of the Page, The Page Layout, Title of the page.  Let’s look at the Create Publishing Page method:   1:   2: private void CreatePublishingPage(SPWeb site, string pageName, string pageLayoutName, string title) 3: { 4: PublishingSite pubSiteCollection = new PublishingSite(site.Site); 5: PublishingWeb pubSite = null; 6: if (pubSiteCollection != null) 7: { 8: // Assign an object to the pubSite variable 9: if (PublishingWeb.IsPublishingWeb(site)) 10: { 11: pubSite = PublishingWeb.GetPublishingWeb(site); 12: } 13: } 14: // Search for the page layout for creating the new page 15: PageLayout currentPageLayout = FindPageLayout(pubSiteCollection, pageLayoutName); 16: // Check or the Page Layout could be found in the collection 17: // if not (== null, return because the page has to be based on 18: // an excisting Page Layout 19: if (currentPageLayout == null) 20: { 21: return; 22: } 23:   24: 25: PublishingPageCollection pages = pubSite.GetPublishingPages(); 26: foreach (PublishingPage p in pages) 27: { 28: //The page allready exists 29: if ((p.Name == pageName)) return; 30:   31: } 32: 33:   34:   35: PublishingPage newPage = pages.Add(pageName, currentPageLayout); 36: newPage.Description = pageName.Replace(".aspx", ""); 37: // Here you can set some properties like: 38: newPage.IncludeInCurrentNavigation = true; 39: newPage.IncludeInGlobalNavigation = true; 40: newPage.Title = title; 41: 42: 43:   44:   45: 46:   47: //build the page 48:   49: 50: switch (pageName) 51: { 52: case "Homer.aspx": 53: checkOut("Courier.aspx", newPage); 54: BuildHomePage(site, newPage); 55: break; 56:   57:   58: default: 59: break; 60: } 61: // newPage.Update(); 62: //Now we can checkin the newly created page to the “pages” library 63: checkin(newPage, pubSite); 64: 65: 66: }     The narrative in what is going on here is: 1.  We need to find out if we are dealing with a Publishing Web.  2.  Get the Page Layout 3.  Create the Page in the pages list. 4.  Based on the page name we build that page.  (Here is where we can add all the methods to build multiple pages.) In the switch we call Build Home Page where all the work is done to add the web parts.  Prior to adding the web parts we need to add references to the two web part projects in the solution. using WeatherWebPart.WeatherWebPart; using CSSharePointCustomCalendar.CustomCalendarWebPart;   We can then reference them in the Build Home Page method.   Let’s look at Build Home Page: 1:   2: private static void BuildHomePage(SPWeb web, PublishingPage pubPage) 3: { 4: // build the pages 5: // Get the web part manager for each page and do the same code as below (copy and paste, change to the web parts for the page) 6: // Part Description 7: SPLimitedWebPartManager mgr = web.GetLimitedWebPartManager(web.Url + "/Pages/Home.aspx", System.Web.UI.WebControls.WebParts.PersonalizationScope.Shared); 8: WeatherWebPart.WeatherWebPart.WeatherWebPart wwp = new WeatherWebPart.WeatherWebPart.WeatherWebPart() { ChromeType = PartChromeType.None, Title = "Todays Weather", AreaCode = "2504627" }; 9: //Dictionary<string, string> wwpDic= new Dictionary<string, string>(); 10: //wwpDic.Add("AreaCode", "2504627"); 11: //setWebPartProperties(wwp, "WeatherWebPart", wwpDic); 12:   13: // Add the web part to a pagelayout Web Part Zone 14: mgr.AddWebPart(wwp, "g_685594D193AA4BBFABEF2FB0C8A6C1DD", 1); 15:   16: CSSharePointCustomCalendar.CustomCalendarWebPart.CustomCalendarWebPart cwp = new CustomCalendarWebPart() { ChromeType = PartChromeType.None, Title = "Corporate Calendar", listName="CorporateCalendar" }; 17:   18: mgr.AddWebPart(cwp, "g_20CBAA1DF45949CDA5D351350462E4C6", 1); 19:   20:   21: pubPage.Update(); 22:   23: } Here is what we are doing: 1.  We got  a reference to the SharePoint Limited Web Part Manager and linked/referenced Home.aspx  2.  Instantiated the a new Weather Web Part and used the Manager to add it to the page in a web part zone identified by ID,  thus the need for a Page Layout where the developer knows the ID’s. 3.  Instantiated the Calendar Web Part and used the Manager to add it to the page. 4. We the called the Publishing Page update method. 5.  Lastly, the Create Publishing Page method checks in the page just created.   Here is a screen shot of the page right after a deploy!       Okay!  I know we could make a home page look much better!  However, I built this whole Integrated solution in less than a day with the caveat that the Green Master was already built!  So what am I saying?  Build you web parts, master pages, etc.  At the very end of the engagement build the pages.  The client will be very happy!  Here is the code for this solution Code

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  • Code Review process

    - by Rubio
    I'm looking for a light-weight code review process. A couple of requirements, the reviewer must be able to do the review alone at the time of his/her choosing (not tied to check-ins), the reviewer must be able to easily find the target code, the review has to leave some document showing what was reviewed. I know there are tools available for code review but I work in a very ridig environment and introducing new tools is not an option. One idea I've been thinking about is to create a new Visual Studio Task List token called REVIEW, and use it to mark the code that needs reviewing. Something like, // REVIEW doe_john: New method, not sure about the exception. Then we would add a Review workitem in TFS (we're using the CMM template). Another possibility, which I would actually prefer, would be to have developers create a TFS Review workitem and add links to code to it, but I don't know if this is possible. Obviously you can add a link to a file, but I'd like to have a link to a particular method.

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  • C#/.NET Little Wonders: The Nullable static class

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Today we’re going to look at an interesting Little Wonder that can be used to mitigate what could be considered a Little Pitfall.  The Little Wonder we’ll be examining is the System.Nullable static class.  No, not the System.Nullable<T> class, but a static helper class that has one useful method in particular that we will examine… but first, let’s look at the Little Pitfall that makes this wonder so useful. Little Pitfall: Comparing nullable value types using <, >, <=, >= Examine this piece of code, without examining it too deeply, what’s your gut reaction as to the result? 1: int? x = null; 2:  3: if (x < 100) 4: { 5: Console.WriteLine("True, {0} is less than 100.", 6: x.HasValue ? x.ToString() : "null"); 7: } 8: else 9: { 10: Console.WriteLine("False, {0} is NOT less than 100.", 11: x.HasValue ? x.ToString() : "null"); 12: } Your gut would be to say true right?  It would seem to make sense that a null integer is less than the integer constant 100.  But the result is actually false!  The null value is not less than 100 according to the less-than operator. It looks even more outrageous when you consider this also evaluates to false: 1: int? x = null; 2:  3: if (x < int.MaxValue) 4: { 5: // ... 6: } So, are we saying that null is less than every valid int value?  If that were true, null should be less than int.MinValue, right?  Well… no: 1: int? x = null; 2:  3: // um... hold on here, x is NOT less than min value? 4: if (x < int.MinValue) 5: { 6: // ... 7: } So what’s going on here?  If we use greater than instead of less than, we see the same little dilemma: 1: int? x = null; 2:  3: // once again, null is not greater than anything either... 4: if (x > int.MinValue) 5: { 6: // ... 7: } It turns out that four of the comparison operators (<, <=, >, >=) are designed to return false anytime at least one of the arguments is null when comparing System.Nullable wrapped types that expose the comparison operators (short, int, float, double, DateTime, TimeSpan, etc.).  What’s even odder is that even though the two equality operators (== and !=) work correctly, >= and <= have the same issue as < and > and return false if both System.Nullable wrapped operator comparable types are null! 1: DateTime? x = null; 2: DateTime? y = null; 3:  4: if (x <= y) 5: { 6: Console.WriteLine("You'd think this is true, since both are null, but it's not."); 7: } 8: else 9: { 10: Console.WriteLine("It's false because <=, <, >, >= don't work on null."); 11: } To make matters even more confusing, take for example your usual check to see if something is less than, greater to, or equal: 1: int? x = null; 2: int? y = 100; 3:  4: if (x < y) 5: { 6: Console.WriteLine("X is less than Y"); 7: } 8: else if (x > y) 9: { 10: Console.WriteLine("X is greater than Y"); 11: } 12: else 13: { 14: // We fall into the "equals" assumption, but clearly null != 100! 15: Console.WriteLine("X is equal to Y"); 16: } Yes, this code outputs “X is equal to Y” because both the less-than and greater-than operators return false when a Nullable wrapped operator comparable type is null.  This violates a lot of our assumptions because we assume is something is not less than something, and it’s not greater than something, it must be equal.  So keep in mind, that the only two comparison operators that work on Nullable wrapped types where at least one is null are the equals (==) and not equals (!=) operators: 1: int? x = null; 2: int? y = 100; 3:  4: if (x == y) 5: { 6: Console.WriteLine("False, x is null, y is not."); 7: } 8:  9: if (x != y) 10: { 11: Console.WriteLine("True, x is null, y is not."); 12: } Solution: The Nullable static class So we’ve seen that <, <=, >, and >= have some interesting and perhaps unexpected behaviors that can trip up a novice developer who isn’t expecting the kinks that System.Nullable<T> types with comparison operators can throw.  How can we easily mitigate this? Well, obviously, you could do null checks before each check, but that starts to get ugly: 1: if (x.HasValue) 2: { 3: if (y.HasValue) 4: { 5: if (x < y) 6: { 7: Console.WriteLine("x < y"); 8: } 9: else if (x > y) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } 17: } 18: else 19: { 20: Console.WriteLine("x > y because y is null and x isn't"); 21: } 22: } 23: else if (y.HasValue) 24: { 25: Console.WriteLine("x < y because x is null and y isn't"); 26: } 27: else 28: { 29: Console.WriteLine("x == y because both are null"); 30: } Yes, we could probably simplify this logic a bit, but it’s still horrendous!  So what do we do if we want to consider null less than everything and be able to properly compare Nullable<T> wrapped value types? The key is the System.Nullable static class.  This class is a companion class to the System.Nullable<T> class and allows you to use a few helper methods for Nullable<T> wrapped types, including a static Compare<T>() method of the. What’s so big about the static Compare<T>() method?  It implements an IComparer compatible comparison on Nullable<T> types.  Why do we care?  Well, if you look at the MSDN description for how IComparer works, you’ll read: Comparing null with any type is allowed and does not generate an exception when using IComparable. When sorting, null is considered to be less than any other object. This is what we probably want!  We want null to be less than everything!  So now we can change our logic to use the Nullable.Compare<T>() static method: 1: int? x = null; 2: int? y = 100; 3:  4: if (Nullable.Compare(x, y) < 0) 5: { 6: // Yes! x is null, y is not, so x is less than y according to Compare(). 7: Console.WriteLine("x < y"); 8: } 9: else if (Nullable.Compare(x, y) > 0) 10: { 11: Console.WriteLine("x > y"); 12: } 13: else 14: { 15: Console.WriteLine("x == y"); 16: } Summary So, when doing math comparisons between two numeric values where one of them may be a null Nullable<T>, consider using the System.Nullable.Compare<T>() method instead of the comparison operators.  It will treat null less than any value, and will avoid logic consistency problems when relying on < returning false to indicate >= is true and so on. Tweet   Technorati Tags: C#,C-Sharp,.NET,Little Wonders,Little Pitfalls,Nulalble

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  • Can't get Minecraft to run on Ubuntu

    - by Dennis
    I have installed JDK and JRE from this tutorial and have tried many methods of starting it up, yet my results are always the same. If any one could please help me I would be very grateful. Exception in thread "Thread-3" java.lang.UnsatisfiedLinkError: /home/dennis/.minecraft/bin/natives/liblwjgl.so: /home/dennis/.minecraft/bin/natives/liblwjgl.so: wrong ELF class: ELFCLASS32 (Possible cause: architecture word width mismatch) at java.lang.ClassLoader$NativeLibrary.load(Native Method) at java.lang.ClassLoader.loadLibrary1(Unknown Source) at java.lang.ClassLoader.loadLibrary0(Unknown Source) at java.lang.ClassLoader.loadLibrary(Unknown Source) at java.lang.Runtime.load0(Unknown Source) at java.lang.System.load(Unknown Source) at org.lwjgl.Sys$1.run(Sys.java:69) at java.security.AccessController.doPrivileged(Native Method) at org.lwjgl.Sys.doLoadLibrary(Sys.java:65) at org.lwjgl.Sys.loadLibrary(Sys.java:81) at org.lwjgl.Sys.<clinit>(Sys.java:98) at net.minecraft.client.Minecraft.F(SourceFile:1853) at aoe.<init>(SourceFile:20) at net.minecraft.client.Minecraft.<init>(SourceFile:77) at anv.<init>(SourceFile:36) at net.minecraft.client.MinecraftApplet.init(SourceFile:36) at net.minecraft.Launcher.replace(Launcher.java:136) at net.minecraft.Launcher$1.run(Launcher.java:79)

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  • Camera lookAt target changes when rotating parent node

    - by Michael IV
    have the following issue.I have a camera with lookAt method which works fine.I have a parent node to which I parent the camera.If I rotate the parent node while keeping the camera lookAt the target , the camera lookAt changes too.That is nor what I want to achieve.I need it to work like in Adobe AE when you parent camera to a null object:when null object is rotated the camera starts orbiting around the target while still looking at the target.What I do currently is multiplying parent's model matrix with camera model matrix which is calculated from lookAt() method.I am sure I need to decompose (or recompose ) one of the matrices before multiplying them .Parent model or camera model ? Anyone here can show the right way doing it ? UPDATE: The parent is just a node .The child is the camera.The parented camera in AfterEffects works like this: If you rotate the parent node while camera looks at the target , the camera actually starts orbiting around the target based on the parent rotation.In my case the parent rotation changes also Camera's lookAt direction which IS NOT what I want.Hope now it is clear .

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  • How do you exclude yourself from Google Analytics on your website using cookies?

    - by Keoki Zee
    I'm trying to set up an exclusion filter with a browser cookie, so that my own visits to my don't show up in my Google Analytics. I tried 3 different methods and none of them have worked so far. I would like help understanding what I am doing wrong and how I can fix this. Method 1 First, I tried following Google's instructions, http://www.google.com/support/analytics/bin/answer.py?hl=en&answer=55481, for excluding traffic by Cookie Content: Create a new page on your domain, containing the following code: <body onLoad="javascript:pageTracker._setVar('test_value');"> Method 2 Next, when that didn't work, I googled around and found this Google thread, http://www.google.com/support/forum/p/Google%20Analytics/thread?tid=4741f1499823fcd5&hl=en, where the most popular answer says to use a slightly different code: SHS Analytics wrote: <body onLoad="javascript:_gaq.push(['_setVar','test_value']);"> Thank you! This has now set a __utmv cookie containing "test_value", whereas the original: pageTracker._setVar('test_value') (which Google is still recommending) did not manage to do that for me (in Mac Safari 5 and Firefox 3.6.8). So I tried this code, but it didn't work for me. Method 3 Finally, I searched StackOverflow and came across this thread, http://stackoverflow.com/questions/3495270/exclude-my-traffic-from-google-analytics-using-cookie-with-subdomain, which suggests that the following code might work: <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setVar', 'exclude_me']); _gaq.push(['_setAccount', 'UA-xxxxxxxx-x']); _gaq.push(['_trackPageview']); // etc... </script> This script appeared in the head element in the example, instead of in the onload event of the body like in the previous 2 examples. So I tried this too, but still had no luck with trying to exclude myself from Google Analytics. Re-iterate question So, I tried all 3 methods above with no success. Am I doing something wrong? How can I exclude myself from my Google Analytics using an exclusion cookie for my browser?

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  • Playing a Song causing WP7 to crash on phone, but not on emulator

    - by Michael Zehnich
    Hi there, I am trying to implement a song into a game that begins playing and continually loops on Windows Phone 7 via XNA 4.0. On the emulator, this works fine, however when deployed to a phone, it simply gives a black screen before going back to the home screen. Here is the rogue code in question, and commenting this code out makes the app run fine on the phone: // in the constructor fields private Song song; // in the LoadContent() method song = Content.Load<Song>("song"); // in the Update() method if (MediaPlayer.GameHasControl && MediaPlayer.State != MediaState.Playing) { MediaPlayer.Play(song); } The song file itself is a 2:53 long, 2.28mb .wma file at 106kbps bitrate. Again this works perfectly on emulator but does not run at all on phone. Thanks for any help you can provide!

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  • Can I input Chinese character in Unity's dash?

    - by Meteor
    I use Ubuntu in Chinese language. And a lot of programme on my Ubuntu have chinese name. I can open it in Terminal. But I can not search them in Unity. Because in Unity's dash, I can only input English, can not use input method. So can not input Chinese character. I use Chinese as my mother language. And I use Chinese input method a lot. Can someone help me to let me input Chinese character in Unity's dash? I really like Ubuntu and want to use it more frequently. Thanks. https://help.ubuntu.com/11.04/ubuntu-help/figures/unity-dash-sample.png

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  • Pointless Code In Your Source

    - by Ali
    I've heard stories of this from senior coders and I've seen some of it myself. It seems that there are more than a few instances of programmers writing pointless code. I will see things like: Method or function calls that do nothing of value. Redundant checks done in a separate class file, object or method. if statements that always evaluate to true. Threads that spin off and do nothing of note. Just to name a few. I've been told that this is because programmers want to intentionally make the code confusing to raise their own worth to the organization or make sure of repeat business in the case of contractual or outsourced work. My question is. Has anyone else seen code like this? What was your conclusion was to why that code was there? If anyone has written code like this, can you share why?

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  • InvokeRequired not reliable?

    - by marocanu2001
    InvalidOperationException: Cross-thread operation not valid: Control 'progressBar' accessed from a thread other than the thread it was created ... Now this is not a nice way to start a day! not even if it's a Monday! So you have seen this and already thought, come on, this is an old one, just ask whether InvokeRequired before calling the method in the control, something like this: if (progressBar.InvokeRequired) {           progressBar.Invoke  ( new MethodInvoker( delegate {  progressBar.Value = 50;    }) ) }else      progressBar.Value = 50;    Unfortunately this was not working the way I would have expected, I got this error, debugged and though in debugging the InvokeRequired had become true , the error was thrown on the branch that did not required Invoke. So there was a scenario where InvokeRequired returned false and still accessing the control was not on the right thread ... Problem was that I kept showing and hiding the little form showing the progressbar. The progressbar was updating on an event  , ProgressChanged and I could not guarantee the little form was loaded by the time the event was thrown. So , spotted the problem, if none of the parents of the control you try to modify is created at the time of the method invoking, the InvokeRequired returns true! That causes your code to execute on the woring thread. Of course, updating UI before the win dow was created is not a legitimate action either, still I would have expected a different error. MSDN: "If the control's handle does not yet exist, InvokeRequired searches up the control's parent chain until it finds a control or form that does have a window handle. If no appropriate handle can be found, the InvokeRequired method returns false. This means that InvokeRequired can return false if Invoke is not required (the call occurs on the same thread), or if the control was created on a different thread but the control's handle has not yet been created." Have  a look at InvokeRequired's implementation: public bool InvokeRequired {     get     {         HandleRef hWnd;         int lpdwProcessId;         if (this.IsHandleCreated)         {             hWnd = new HandleRef(this, this.Handle);         }         else         {             Control wrapper = this.FindMarshallingControl();             if (!wrapper.IsHandleCreated)             {                 return false; // <==========             }             hWnd = new HandleRef(wrapper, wrapper.Handle);         }         int windowThreadProcessId = SafeNativeMethods.GetWindowThreadProcessId(hWnd, out lpdwProcessId);         int currentThreadId = SafeNativeMethods.GetCurrentThreadId();         return (windowThreadProcessId != currentThreadId);     } } Here 's a good article about this and a workaround http://www.ikriv.com/en/prog/info/dotnet/MysteriousHang.html

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  • CodePlex Daily Summary for Wednesday, February 29, 2012

    CodePlex Daily Summary for Wednesday, February 29, 2012Popular ReleasesZXing.Net: ZXing.Net 0.4.0.0: sync with rev. 2196 of the java version important fix for RGBLuminanceSource generating barcode bitmaps Windows Phone demo client (only tested with emulator, because I don't have a Windows Phone) Barcode generation support for Windows Forms demo client Webcam support for Windows Forms demo clientOrchard Project: Orchard 1.4: Please read our release notes for Orchard 1.4: http://docs.orchardproject.net/Documentation/Orchard-1-4-Release-NotesFluentData -Micro ORM with a fluent API that makes it simple to query a database: FluentData version 1.2: New features: - QueryValues method - Added support for automapping to enumerations (both int and string are supported). Fixed 2 reported issues.NetSqlAzMan - .NET SQL Authorization Manager: 3.6.0.15: 3.6.0.15 28-Feb-2012 • Fix: The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state. Work Item 10435: http://netsqlazman.codeplex.com/workitem/10435 • Fix: Made StorageCache thread safe. Thanks to tangrl. • Fix: Members property of SqlAzManApplicationGroup is not functioning. Thanks to tangrl. Work Item 10267: http://netsqlazman.codeplex.com/workitem/10267 • Fix: Indexer are making database calls. Thanks to t...SCCM Client Actions Tool: Client Actions Tool v1.1: SCCM Client Actions Tool v1.1 is the latest version. It comes with following changes since last version: Added stop button to stop the ongoing process. Added action "Query update status". Added option "saveOnlineComputers" in config.ini to enable saving list of online computers from last session. Default value for "LatestClientVersion" set to SP2 R3 (4.00.6487.2157). Wuauserv service manual startup mode is considered healthy on Windows 7. Errors are now suppressed in checkReleases...Document.Editor: 2012.1: Whats new for Document.Editor 2012.1: Improved Recent Documents list Improved Insert Shape Improved Dialogs Minor Bug Fix's, improvements and speed upsKinect PowerPoint Control: Kinect PowerPoint Control v1.1: Updated for Kinect SDK 1.0.SharpCompress - a fully native C# library for RAR, 7Zip, Zip, Tar, GZip, BZip2: SharpCompress 0.8: API Updates: SOLID Extract Method for Archives (7Zip and RAR). ExtractAllEntries method on Archive classes will extract archives as a streaming file. This can offer better 7Zip extraction performance if any of the entries are solid. The IsSolid method on 7Zip archives will return true if any are solid. Removed IExtractionListener was removed in favor of events. Unit tests show example. Bug fixes: PPMd passes tests plus other fixes (Thanks Pavel) Zip used to always write a Post Descri...Social Network Importer for NodeXL: SocialNetImporter(v.1.3): This new version includes: - Download new networks for Facebook fan pages. - New options for downloading more posts - Bug fixes To use the new graph data provider, do the following: Unzip the Zip file into the "PlugIns" folder that can be found in the NodeXL installation folder (i.e "C:\Program Files\Social Media Research Foundation\NodeXL Excel Template\PlugIns") Open NodeXL template and you can access the new importer from the "Import" menuASP.NET REST Services Framework: Release 1.1 - Standard version: Beginning from v1.1 the REST-services Framework is compatible with ASP.NET Routing model as well with CRUD (Create, Read, Update, and Delete) principle. These two are often important when building REST API functionality within your application. It also includes ability to apply Filters to a class to target all WebRest methods, as well as some performance enhancements. New version includes Metadata Explorer providing ability exploring the existing services that becomes essential as the number ...SQL Live Monitor: SQL Live Monitor 1.31: A quick fix to make it this version work with SQL 2012. Version 2 already has 2012 working, but am still developing the UI in version 2, so this is just an interim fix to allow user to monitor SQL 2012.DotNet.Highcharts: DotNet.Highcharts 1.1 with Examples: Fixed small bug in JsonSerializer about the numbers represented as string. Fixed Issue 310: decimal values don't work Fixed Issue 345: Disable Animation Refactored Highcharts class. Implemented Issue 341: More charts on one page. Added new class Container which can combine and display multiple charts. Usage: new Container(new[] { chart1, chart2, chart3, chart4 }) Implemented Feature 302: Inside an UpdatePanel - Added method (InFunction) which create the Highchart inside JavaScript f...Content Slider Module for DotNetNuke: 01.02.00: This release has the following updates and new features: Feature: One-Click Enabling of Pager Setting Feature: Cache Sliders for Performance Feature: Configurable Cache Setting Enhancement: Transitions can be Selected Bug: Secure Folder Images not Viewable Bug: Sliders Disappear on Postback Bug: Remote Images Cause Error Bug: Deleted Images Cause Error System Requirements DotNetNuke v06.00.00 or newer .Net Framework v3.5 SP1 or newer SQL Server 2005 or newerImage Resizer for Windows: Image Resizer 3 Preview 3: Here is yet another iteration toward what will eventually become Image Resizer 3. This release is stable. However, I'm calling it a preview since there are still many features I'd still like to add before calling it complete. Updated on February 28 to fix an issue with installing on multi-user machines. As usual, here is my progress report. Done Preview 3 Fix: 3206 3076 3077 5688 Fix: 7420 Fix: 7527 Fix: 7576 7612 Preview 2 6308 6309 Fix: 7339 Fix: 7357 Preview 1 UI...Finestra Virtual Desktops: 2.5.4500: This is a bug fix release for version 2.5. It fixes several things and adds a couple of minor features. See the 2.5 release notes for more information on the major new features in that version. Important - If Finestra crashes on startup for you, you must install the Visual C++ 2010 runtime from http://www.microsoft.com/download/en/details.aspx?id=5555. Fixes a bug with window animations not refreshing the screen on XP and with DWM off Fixes a bug with with crashing on XP due to a bug in t...AutoExpandOver - Show popup on mouseover, focus, click in Silverlight: AutoExpandOver 2.1: Many fixes. All leaks are gone. Features added.FileSquirrel: FileSquirrel Alpha 1.2.1 32bit and x64: FileSquirrel Alpha 1.2.1Publishing SCSM Work Item to a Sharepoint Calendar: PublishWI command line tool (Updated): Updated for SCSM 2012 (RC) PublishWI command line tool Usage: PublishWI.exe WIID URL CalendarName WIID: ID of the Work Item to publish (for example, CR3333) URL: URL of the SharePoint site, such as http://www.sharepoint.com CalendarName: The name of the sharepoint calendar to publish WI to.HttpRider - Tool for Web Site Performance and Stress Tests: HttpRider 1.0: Please let me know any issues you face. ThanksMedia Companion: MC 3.432b Release: General Now remembers window location. Catching a few more exceptions when an image is blank TV A couple of UI tweaks Movies Fixed the actor name displaying HTML Fixed crash when using Save files as "movie.nfo", "movie.tbn", & "fanart.jpg" New CSV template for HTML output function Added <createdate> tag for HTML output A couple of UI tweaks Known Issues Multiepisodes are not handled correctly in MC. The created nfo is valid, but they are not displayed in MC correctly & saving the...New Projects.NET Implementation of Extensions for Financial Services: NXFS is planned to be a compliant .Net implementation of CEN/XFS (currently version 3.20) to overcome some deficits of native implementation such as not supporting highly productive programming languages (like C#) and supporting only Windows XP and x86 platform.BigCoder WebMaster Tools: BigCoder WebMaster ToolsBigCoder Whois Program: BigCoder Whois ProgrambiscuitCMS: biscuitCMS makes it easier for <target user group> to <activity>. You'll no longer have to <activity>. It's developed in <programming language>. BridgeSeismic: BridgeSeismicData Normilizer: Decomposer for SQL fact tables, for BI projectsDownload Indexed Cache: "Download Indexed Cache" implements the Bing API Version 2 to retrieve content indexed within the Bing Cache to support the "Search Engine Reconnaissance" section of the OWASP Testing Guide v3. FITSExplorer: FITS Explorer is designed to allow astronomers to quickly and easily browse and preview the image and metadata stored in FITS files. The application was developed using primarily WPF and C#, with some low-level data manipulation routines written in C++ for high-performance.ICalSync: icalsyncLeague Manager: Nosso gerenciador de campeonatosLemcube SISTRI: interfacciamento ai servizi di Interoperabilità SIS.: Lemcube SISTRI: interfacciamento ai servizi di Interoperabilità SIS.LittlePluginLib: A small plugin system based on the .net framework 3.5Log reading: Reading and parsing huge log files, download from ftp server and upload to msql database.Mail Aggregator Service: To address the problem of being 'spammed' by your own alert emails this service was created to group/batch mail messages sent to the same 'to' address. It can integrate into QuickMon or even be used as a stand-alone tool to send out alert notifications. MangoTicTacToe: Demo application of a simple Silverlight game for Windows Phone 7. This tictactoe game features some of the most basics requirements for making a Silverlight game for Windows Phone 7.MonkeyButt: Web alternatives to commercial software like Facebook and Google.PizzaSoft: PizzaSoftproject: project demoSharePoint 2010 Automatically Generated Solution Demo: In this demo project I show how to generate Sandboxed Solutions by code at runtime.SoftService: Software ServiceSPAdmin: SharePoint WarmUp ToolSSASNet: SSASNetSSIS Data Masker: A SSIS Data Flow Transformation Component To Provide Basic Data Masking Capabilities.UpiGppf: This is a high shcool projectXMPP/Media Library for .NET and Windows Phone 7.5: .NET libraries for XMPP, TLS, RTP, STUN, SOCKS and more for windows and windows phone.

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  • Introducing jLight &ndash; Talking to the DOM using Silverlight and jQuery.

    - by Timmy Kokke
    Introduction With the recent news about Silverlight on the Windows Phone and all the great Out-Of-Browser features in the upcoming Silverlight 4 you almost forget Silverlight is a browser plugin. It most often runs in a web browser and often as a control. In many cases you need to communicate with the browser to get information about textboxes, events or details about the browser itself. To do this you can use JavaScript from Silverlight. Although Silverlight works the same on every browser, JavaScript does not and it won’t be long before problems arise. To overcome differences in browser I like to use jQuery. The only downside of doing this is that there’s a lot more code needed that you would normally use when you write jQuery in JavaScript. Lately, I had to catch changes is the browser scrollbar and act to the new position. I also had to move the scrollbar when the user dragged around in the Silverlight application. With jQuery it was peanuts to get and set the right attributes, but I found that I had to write a lot of code on Silverlight side.  With a few refactoring I had a separated out the plumbing into a new class and could call only a few methods on that to get the same thing done. The idea for jLight was born. jLight vs. jQuery The main purpose of jLight is to take the ease of use of jQuery and bring it into Silverlight for handling DOM interaction. For example, to change the text color of a DIV to red, in jQuery you would write: jQuery("div").css("color","red"); In jLight the same thing looks like so: jQuery.Select("div").Css("color","red");   Another example. To change the offset in of the last SPAN you could write this in jQuery : jQuery("span:last").offset({left : 10, top : 100});   In jLight this would do the same: jQuery.Select("span:last").Offset(new {left = 10, top = 100 });   Callbacks Nothing too special so far. To get the same thing done using the “normal” HtmlPage.Window.Eval, it wouldn’t require too much effort. But to wire up a handler for events from the browser it’s a whole different story. Normally you need to register ScriptMembers, ScriptableTypes or write some code in JavaScript. jLight takes care of the plumbing and provide you with an simple interface in the same way jQuery would. If you would like to handle the scroll event of the BODY of your html page, you’ll have to bind the event using jQuery and have a function call back to a registered function in Silverlight. In the example below I assume there’s a method “SomeMethod” and it is registered as a ScriptableObject as “RegisteredFromSilverlight” from Silverlight.   jQuery("body:first").scroll(function() { var sl = document.getElementbyId("SilverlightControl"); sl.content.RegisteredFromSilverlight.SomeMethod($(this)); });       Using jLight  in Silverlight the code would be even simpler. The registration of RegisteredFromSilverlight  as ScriptableObject can be omitted.  Besides that, you don’t have to write any JavaScript or evaluate strings with JavaScript.   jQuery.Select("body:first").scroll(SomeMethod);   Lambdas Using a lambda in Silverlight can make it even simpler.  Each is the jQuery equivalent of foreach in C#. It calls a function for every element found by jQuery. In this example all INPUT elements of the text type are selected. The FromObject method is used to create a jQueryObject from an object containing a ScriptObject. The Val method from jQuery is used to get the value of the INPUT elements.   jQuery.Select("input:text").Each((element, index) => { textBox1.Text += jQueryObject.FromObject(element).Val(); return null; });   Ajax One thing jQuery is often used for is making Ajax calls. Making calls to services to external services can be done from Silverlight, but as easy as using jQuery. As an example I would like to show how jLight does this. Below is the entire code behind. It searches my name on twitter and shows the result. This example can be found in the source of the project. The GetJson method passes a Silverlight JsonValue to a callback. This callback instantiates Twit objects and adds them to a ListBox called TwitList.   public partial class DemoPage2 : UserControl { public DemoPage2() { InitializeComponent(); jQuery.Load(); }   private void CallButton_Click(object sender, RoutedEventArgs e) { jQuery.GetJson("http://search.twitter.com/search.json?lang=en&q=sorskoot", Done); }   private void Done(JsonValue arg) { var tweets = new List<Twit>(); foreach (JsonObject result in arg["results"]) { tweets.Add(new Twit() { Text = (string)result["text"], Image = (string)result["profile_image_url"], User = (string)result["from_user"] } ); } TwitList.ItemsSource = tweets; } }   public class Twit { public string User { get; set; } public string Image { get; set; } public string Text { get; set; } }   Conclusion Although jLight is still in development it can be used already.There isn’t much documentation yet, but if you know jQuery jLight isn’t very hard to use.  If you would like to try it, please let me know what you think and report any problems you run in to. jLight can be found at:   http://jlight.codeplex.com

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  • Best practices for logging and tracing in .NET

    - by Levidad
    I've been reading a lot about tracing and logging, trying to find some golden rule for best practices in the matter, but there isn't any. People say that good programmers produce good tracing, but put it that way and it has to come from experience. I've also read similar questions in here and through the internet and they are not really the same thing I am asking or do not have a satisfying answer, maybe because the questions lack some detail. So, folks say that tracing should sort of replicate the experience of debugging the application in cases where you can't attach a debugger. It should provide enough context so that you can see which path is taken at each control point in the application. Going deeper, you can even distinguish between tracing and event logging, in that "event logging is different from tracing in that it captures major states rather than detailed flow of control". Now, say I want to do my tracing and logging using only the standard .NET classes, those in the System.Diagnostics namespace. I figured that the TraceSource class is better for the job than the static Trace class, because I want to differentiate among the trace levels and using the TraceSource class I can pass in a parameter informing the event type, while using the Trace class I must use Trace.WriteLineIf and then verify things like SourceSwitch.TraceInformation and SourceSwitch.TraceErrors, and it doesn't even have properties like TraceVerbose or TraceStart. With all that in mind, would you consider a good practice to do as follows: Trace a "Start" event when begining a method, which should represent a single logical operation or a pipeline, along with a string representation of the parameter values passed in to the method. Trace an "Information" event when inserting an item into the database. Trace an "Information" event when taking one path or another in an important if/else statement. Trace a "Critical" or "Error" in a catch block depending on weather this is a recoverable error. Trace a "Stop" event when finishing the execution of the method. And also, please clarify when best to trace Verbose and Warning event types. If you have examples of code with nice trace/logging and are willing to share, that would be excelent. Note: I've found some good information here, but still not what I am looking for: http://msdn.microsoft.com/en-us/magazine/ff714589.aspx Thanks in advance!

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