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  • C#- move a shape to a point which is half way from the top of the form

    - by hello-all
    Hello all, Here I have to create a diamond using drawlines method and make it move horizontally along a path that is half way from the top of the form. I created a diamond and it is moving horizontally, but i want it to start moving from a position which is half way from the top of the form. This is the code to create a diamond, private void Form1_Paint(object sender, PaintEventArgs e) { Graphics g = e.Graphics; Point p1 = new Point(5+x, 0); Point p2 = new Point(10+x, 5); Point p3 = new Point(5+x, 10); Point p4 = new Point(0+x, 5); Point[] ps = { p1, p2, p3, p4, p1 }; Pen p_yellow = new Pen(Color.Yellow, 5); g.DrawLines(p_yellow, ps); this.BackColor = System.Drawing.Color.DarkBlue; } I can make it move using the timer and following is the code, private void timer1_Tick(object sender, EventArgs e) { if (x < 500) x += 2; else timer1.Enabled = false; this.Invalidate(); } please tell me how to bring the diamond to a point which is half way from the top of the form?

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  • Winsock WSAAsyncSelect sending without an infinite buffer

    - by Xexr
    Hi, This is more of a design question than a specific code question, I'm sure I am missing the obvious, I just need another set of eyes. I am writing a multi-client server based on WSAAsyncSelect, each connection is made into an object of a connection class I have written which contains associated settings and buffers etc. My question concerns FD_WRITE, I understand how it operates: One FD_WRITE is sent immediately after a connection is established. Thereafter, you should send until WSAEWOULDBLOCK is received at which point you store what is left to send in a buffer, and wait to be told that it is ok to send again. This is where I have a problem, how large do I make this holding buffer within each connections object? The amount of time until a new FD_WRITE is received is unknown, I could be attempting to send a lot of stuff during this period, all the time adding to my outgoing buffer. If I make the buffer dynamic, memory usage could spiral out of control if for whatever reason, I am unable to send() and reduce the buffer. So my question is how do you generally handle this situation? Note I am not talking about the network buffer itself which winsock uses, but one of my own creation used to "queue" up sends. Hope I explained that well enough, thanks all!

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  • handle large Parcelable ArrayList in Android

    - by Gal Ben-Haim
    I'm developing an Android app that is a client to a JSON webservice API. I have classes of resource objects (some are nested) and I pass results from an IntentService that access the webserive using the Parcelable interface for all the resource classes. the webservice returns arrays or results that can be potentially large (because of the nesting, for example, a post object also contains comments array, each comment also contains a user object). currently I'm either inserting the results into a SQlite database or displaying them in a ListView. (my relevant methods are accepting ArrayList<resourceClass> as arguments). (some data need to be persistent stored and some should not). since I don't know what size of lists I can handle this way without reaching the memory limits, is this a good practice ? is it a better idea to save the parsed JSON to a local file immediately and pass the file path to the ResultReceiver, then either insert to database from that file or display the data ? is there a better way to handle this ? btw - I'm parsing the JSON as a stream with Gson's Reader so there shouldn't be memory issues at that stage.

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  • Strange FileNotFoundException occuring on production server in console application

    - by thmsn
    Hi I have an application that works fine in my dev enviroment, but throws weird errors in the production enviroment, I checked the version of .net on my dev machine aswell as the production server , they both run 3.5.30729.01. The exception I get is a System.IO.FileNotFoundException. StackTrace: at System.Diagnostics.FileVersionInfo.GetVersionInfo(String fileName) at System.Configuration.ClientConfigPaths.SetNamesAndVersion(String applicationFilename, Assembly exeAssembly, Boolean isHttp) at System.Configuration.ClientConfigPaths..ctor(String exePath, Boolean includeUserConfig) at System.Configuration.ClientConfigPaths.GetPaths(String exePath, Boolean includeUserConfig) at System.Configuration.ClientConfigurationHost.get_ConfigPaths() at System.Configuration.ClientConfigurationHost.RequireCompleteInit(IInternalConfigRecord record) at System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject) at System.Configuration.BaseConfigurationRecord.GetSection(String configKey) at System.Configuration.ClientConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection(String sectionName) at System.Configuration.ConfigurationManager.GetSection(String sectionName) at System.Configuration.PrivilegedConfigurationManager.GetSection(String sectionName) at System.DirectoryServices.SearchResultCollection.ResultsEnumerator..ctor(SearchResultCollection results, String parentUserName, String parentPassword, AuthenticationTypes parentAuthenticationType) at System.DirectoryServices.SearchResultCollection.GetEnumerator() at System.DirectoryServices.DirectorySearcher.FindOne() Yesterday the error just went away, and today the error is occuring again. I tried using reflector and it appears to have something to do with config files or user config files. any ideas?

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  • Working with datetime type in Quickbooks My Time files

    - by jakemcgraw
    I'm attempting to process Quickbooks My Time imt files using PHP. The imt file is a plaintext XML file. I've been able to use the PHP SimpleXML library with no issues but one: The numeric representations of datetime in the My Time XML files is something I've never seen before: <object type="TIMEPERIOD" id="z128"> <attribute name="notes" type="string"></attribute> <attribute name="start" type="date">308073428.00000000000000000000</attribute> <attribute name="running" type="bool">0</attribute> <attribute name="duration" type="double">3600</attribute> <attribute name="datesubmitted" type="date">310526237.59616601467132568359</attribute> <relationship name="activity" type="1/1" destination="ACTIVITY" idrefs="z130"></relationship> </object> You can see that attritube[@name='start'] has a value of: 308073428.00000000000000000000 This is not Excel based method of storage 308,073,428 is too many days since 1900-01-00 and it isn't Unix Epoch either. So, my question is, has anyone ever seen this type of datetime representation?

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  • C# Attribute XmlIgnore and XamlWriter class - XmlIgnore not working

    - by Horst Walter
    I have a class, containing a property Brush MyBrush marked as [XmlIgnore]. Nevertheless it is serialized in the stream causing trouble when trying to read via XamlReader. I did some tests, e.g. when changing the visibility (to internal) of the Property it is gone in the stream. Unfortunately I cannot do this in my particular scenario. Did anybody have the same issue and? Do you see any way to work around this? Remark: C# 4.0 as far I can tell This is a method from my Unit Test where I do test the XamlSerialization: // buffer to a StringBuilder StringBuilder sb = new StringBuilder(); XmlWriter writer = XmlWriter.Create(sb, settings); XamlDesignerSerializationManager manager = new XamlDesignerSerializationManager(writer) {XamlWriterMode = XamlWriterMode.Expression}; XamlWriter.Save(testObject, manager); xml = sb.ToString(); Assert.IsTrue(!String.IsNullOrEmpty(xml) && !String.IsNullOrEmpty(xml), "Xaml Serialization failed for " + testObject.GetType() + " no xml string available"); xml = sb.ToString(); MemoryStream ms = xml.StringToStream(); object root = XamlReader.Load(ms); Assert.IsTrue(root != null, "After reading from MemoryStream no result for Xaml Serialization"); In one of my classes I use the Property Brush. In the above code this Unit Tests fails because of a Brush object not serializable is the value. When I remove the Setter (as below, the Unit Test passes. Using the XmlWriter (basically same test as above) it works. In the StringBuffer sb I can see that Property Brush is serialized when the Setter is there and not when removed (most likely another check ignoring the Property because of no setter). Other Properties with [XmlIgnore] are ignored as intended. [XmlIgnore] public Brush MyBrush { get { ..... } // removed because of problem with Serialization // set { ... } }

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  • MS Access to sql server searching

    - by malou17
    How to use this code if we are going to use sql server database becaUSE in this code we used MS Access as the database private void btnSearch_Click(object sender, System.EventArgs e) { String pcode = txtPcode.Text; int ctr = productsDS1.Tables[0].Rows.Count; int x; bool found = false; for (x = 0; x<ctr; x++) { if (productsDS1.Tables[0].Rows[x][0].ToString() == pcode) { found = true; break; } } if (found == true) { txtPcode.Text = productsDS1.Tables[0].Rows[x][0].ToString(); txtDesc.Text = productsDS1.Tables[0].Rows[x][1].ToString(); txtPrice.Text = productsDS1.Tables[0].Rows[x][2].ToString(); } else { MessageBox.Show("Record Not Found"); } private void btnNew_Click(object sender, System.EventArgs e) { int cnt = productsDS1.Tables[0].Rows.Count; string lastrec = productsDS1.Tables[0].Rows[cnt][0].ToString(); int newpcode = int.Parse(lastrec) + 1; txtPcode.Text = newpcode.ToString(); txtDesc.Clear(); txtPrice.Clear(); txtDesc.Focus(); here's the connectionstring Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Registry Path=;Jet OLEDB:Database Locking Mode=0;Data Source="J:\2009-2010\1st sem\VC#\Sample\WindowsApplication_Products\PointOfSales.mdb"

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  • iPhone question: How can I add a button to a tableview cell?

    - by Jake
    Hi guys, Little background, the table view is filled by a fetchedResultsController which fills the table view with Strings. Now I'm trying to add a button next to each String in each tableview cell. So far, I've been trying to create a button in my configureCell:atIndexPath method and then add that button as a subview to the table cell's content view, but for some reason the buttons do not show up. Below is the relevant code. If anyone wants more code posted, just ask and I'll put up whatever you want. Any help is greatly appreciated. - (void)configureCell:(UITableViewCell *)cell atIndexPath:(NSIndexPath *)indexPath { // get object that has the string that will be put in the table cell Task *task = [fetchedResultsController objectAtIndexPath:indexPath]; //make button UIButton *button = [[UIButton buttonWithType:UIButtonTypeRoundedRect] retain]; [button setTitle:@"Check" forState:UIControlStateNormal]; [button setTitle:@"Checked" forState:UIControlStateHighlighted]; //set the table cell text equal to the object's property cell.textLabel.text = [task taskName]; //addbutton as a subview [cell.contentView addSubview:button]; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease]; } // Configure the cell. [self configureCell:cell atIndexPath:indexPath]; return cell; }

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  • How to keep your unit test Arrange step simple and still guarantee DDD invariants ?

    - by ian31
    DDD recommends that the domain objects should be in a valid state at any time. Aggregate roots are responsible for guaranteeing the invariants and Factories for assembling objects with all the required parts so that they are initialized in a valid state. However this seems to complicate the task of creating simple, isolated unit tests a lot. Let's assume we have a BookRepository that contains Books. A Book has : an Author a Category a list of Bookstores you can find the book in These are required attributes : a book has to have an author, a category and at least a book store you can buy the book from. There's likely to be a BookFactory since it is quite a complex object, and the Factory will initialize the Book with at least all the mentioned attributes. Now we want to unit test a method of the BookRepository that returns all the Books. To test if the method returns the books, we have to set up a test context (the Arrange step in AAA terms) where some Books are already in the Repository. If the only tool at our disposal to create Book objects is the Factory, the unit test now also uses and is dependent on the Factory and inderectly on Category, Author and Store since we need those objects to build up a Book and then place it in the test context. Would you consider this is a dependency in the same way that in a Service unit test we would be dependent on, say, a Repository that the Service would call ? How would you solve the problem of having to re-create a whole cluster of objects in order to be able to test a simple thing ? How would you break that dependency and get rid of all these attributes we don't need in our test ? By using mocks or stubs ? If you mock up things a Repository contains, what kind of mock/stubs would you use as opposed to when you mock up something the object under test talks to or consumes ?

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  • ASP.NET MVC 2 - How do I use DropDownListFor ?

    - by SLC
    I have a simple model / view with things like Username, Password etc. and use helpers fine to hook it up. I now have a field called "NumberOfChildren". I want to store a number in it (int) and I want it render a dropdown box containing "None", "1", "2" etc. My thoughts would be that the model would have a list or a method that returns a list, so I can specify the values such as NumberOfChildren_List that I put the data into, and then DropDownListFor pulls that list and renders it, matching the value to the value of the item in the dropdown. However after spending about 30 minutes on trying to figure out how on earth it works, I gave up and decided to ask here. Any ideas? Edit: Here's some code... <%: Html.DropDownListFor(m => m.NumberOfChildren, new SelectList(Model.NumberOfChildrenListValues))%> and in the model [Required] [DisplayName("How many children do you have?")] public string NumberOfChildren { get; set; } public IEnumerable<string> NumberOfChildrenListValues { get { List<string> list = new List<string>() { "None", "1", "2" }; return list; } set { } } I get an object not set to instance of object error though. Ideas?

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  • two controllers in one layout, rails 3

    - by Grizlord
    Okay, I have two models, a recipe model and a category model. In my layout(application.html.erb) I have a main container div that "yields" the recipes index action. I'm trying to list all the category names as links in a side bar(also a div) by iterating over them in an unordered list. When you click one of the links it will go to the category show page which will then list all the recipes in that category. Here is how I'm trying to list the links in - <div class="container" id="categories"> <% for category in @categories %> <ul> <li><%= link_to category.name, category %></li> </ul> <% end %> </div> The problem is I get a NoMethodError - You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each It is not retrieving the records from the model. Any suggestions on how to get this done would be greatly appreciated. I tried to render a partial as some of the other similar posts have said but still get the same error. This is the exact error - NoMethodError in Recipes#index Showing /Users/grizlord/Rails/recipe2/app/views/layouts/application.html.erb where line #39 raised: You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each Extracted source (around line #39): 36: </div> 37: <div class="container" id="categories"> 38: Browse by Category 39: <% for category in @categories %> 40: <ul> 41: <li><%= link_to category.name, category %></li> 42: </ul>

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  • LoginControl not working correctly with Firefox, requires double login attempt.

    - by CmdrTallen
    Any idea why LoginControl requires users authenticate twice with FireFox but works correctly (once) with IE? I am using a custom MembershipProvider and RoleProvider, if that matters. Authentication portion of my web.config; <authentication mode="Forms"> <forms timeout="50000000" protection="All" requireSSL="false" slidingExpiration="true" cookieless="AutoDetect" domain="" enableCrossAppRedirects="true"> <credentials passwordFormat="SHA1" /> </forms> </authentication> Membership section; <membership defaultProvider="CustomMembershipProvider"> <providers> <add name="CustomMembershipProvider" type="CustomCrateMembershipProvider" connectionString="" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="true" applicationName="/" requiresUniqueEmail="true" passwordFormat="Hashed" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="5" minRequiredNonalphanumericCharacters="1" passwordAttemptWindow="10" passwordStrengthRegularExpression=""/> </providers> </membership> <roleManager defaultProvider="CustomRoleProvider" enabled="true"> <providers> <add name="CustomRoleProvider" type="CustomRoleProvider"/> </providers> </roleManager> Only code behind related to login; protected void OnLoggedIn(object sender, EventArgs e) { } protected void OnLoggingOut(object sender, EventArgs e) { }

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  • Creating a blocking Queue<T> in .NET?

    - by spoon16
    I have a scenario where I have multiple threads adding to a queue and multiple threads reading from the same queue. If the queue reaches a specific size all threads that are filling the queue will be blocked on add until an item is removed from the queue. The solution below is what I am using right now and my question is: How can this be improved? Is there an object that already enables this behavior in the BCL that I should be using? internal class BlockingCollection<T> : CollectionBase, IEnumerable { //todo: might be worth changing this into a proper QUEUE private AutoResetEvent _FullEvent = new AutoResetEvent(false); internal T this[int i] { get { return (T) List[i]; } } private int _MaxSize; internal int MaxSize { get { return _MaxSize; } set { _MaxSize = value; checkSize(); } } internal BlockingCollection(int maxSize) { MaxSize = maxSize; } internal void Add(T item) { Trace.WriteLine(string.Format("BlockingCollection add waiting: {0}", Thread.CurrentThread.ManagedThreadId)); _FullEvent.WaitOne(); List.Add(item); Trace.WriteLine(string.Format("BlockingCollection item added: {0}", Thread.CurrentThread.ManagedThreadId)); checkSize(); } internal void Remove(T item) { lock (List) { List.Remove(item); } Trace.WriteLine(string.Format("BlockingCollection item removed: {0}", Thread.CurrentThread.ManagedThreadId)); } protected override void OnRemoveComplete(int index, object value) { checkSize(); base.OnRemoveComplete(index, value); } internal new IEnumerator GetEnumerator() { return List.GetEnumerator(); } private void checkSize() { if (Count < MaxSize) { Trace.WriteLine(string.Format("BlockingCollection FullEvent set: {0}", Thread.CurrentThread.ManagedThreadId)); _FullEvent.Set(); } else { Trace.WriteLine(string.Format("BlockingCollection FullEvent reset: {0}", Thread.CurrentThread.ManagedThreadId)); _FullEvent.Reset(); } } }

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  • Issue calling superclass method in subclass constructor

    - by stormin986
    I get a NullPointerException calling a Superclass Method in Subclass Inner Class Constructor... What's the Deal? In my application's main class (subclass of Application), I have a public inner class that simply contains 3 public string objects. In the parent class I declare an object of that inner class. public class MainApplication extends Application { public class Data { public String x; public String y; public String z; } private Data data; MainApplication() { data = new Data() data.x = SuperClassMethod(); } } After I instantiate the object in the constructor, I get a runtime error when I try to assign a value in the inner class with a superclass method. Any idea what's up here?? Can you not call superclass methods in the subclass constructor? ** Edit ** Original question was about inner class member assignment in outer class constructor. Turned out the issue was with calling a superclass method in the class's constructor. It was giving me a null pointer exception. Thus, the question has changed.

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  • iphone crash log with dSym not loading debug information

    - by AngeDeLaMort
    Hello, I was trying to see why my application crashed on the device (iPhone) using the dSym generated along the executable (in ad hoc), but I don't know why, there isn't any useful information. It seems that "Organizer" is able to find the appropriate dSym and translate some data into more readable one, but when it comes to my application, I just have an address. Since I know how to reproduce it, I've tried to setup my build so it can help me in the future. So, I've tried to find if I had all the proper flags set int the project build properties and everything seems fine. So after doing some research, it seems that all information are stripped during link time and the dSym seems completely useless. I've played with some flags, but nothing changed. So, is there something special to do in order to get the crash file human readable? Or is it impossible in the ad hoc setting? The closest thing near to work that I've done was to build a debug version and look up the address in it. At least it seems to give the right file. So, I made a sample app and here what I have: (the line I want is #4): Thread 0 Crashed: 0 libobjc.A.dylib 0x00003ebc objc_msgSend + 20 1 UIKit 0x0005c970 -[UIView dealloc] + 60 2 UIKit 0x0005c840 -[UIImageView dealloc] + 76 3 CoreFoundation 0x0003963a -[NSObject release] + 28 4 MyApplication 0x000046a6 0x1000 + 13990 5 UIKit 0x00069750 -[UIViewController view] + 44 6 MyApplication 0x000053fa 0x1000 + 17402 The crash is made using 2 successive releases on an object. Thanks in advance.

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  • Making it look like the computer is thinking in TicTacToe game

    - by rage
    here is a slice of code that i've written in VB.net Private Sub L00_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles L00.Click, L01.Click, L02.Click, L03.Click, L10.Click, L11.Click, L12.Click, L13.Click, L20.Click, L21.Click, L22.Click, L23.Click, L30.Click, L31.Click, L32.Click, L33.Click Dim ticTac As Label = CType(sender, Label) Dim strRow As String Dim strCol As String 'Once a move is made, do not allow user to change whether player/computer goes first, because it doesn't make sense to do so since the game has already started. ComputerFirstStripMenuItem.Enabled = False PlayerFirstToolStripMenuItem.Enabled = False 'Check to make sure clicked tile is a valid tile i.e and empty tile. If (ticTac.Text = String.Empty) Then ticTac.Text = "X" ticTac.ForeColor = ColorDialog1.Color ticTac.Tag = 1 'After the player has made his move it becomes the computers turn. computerTurn(sender, e) Else MessageBox.Show("Please pick an empty tile to make next move", "Invalid Move") End If End Sub Private Sub computerTurn(ByVal sender As System.Object, ByVal e As System.EventArgs) Call Randomize() row = Int(4 * Rnd()) col = Int(4 * Rnd()) 'Check to make sure clicked tile is a valid tile i.e and empty tile. If Not ticTacArray(row, col).Tag = 1 And Not ticTacArray(row, col).Tag = 4 Then ticTacArray(row, col).Text = "O" ticTacArray(row, col).ForeColor = ColorDialog2.Color ticTacArray(row, col).Tag = 4 checkIfGameOver(sender, e) Else 'Some good ole pseudo-recursion(doesn't require a base case(s)). computerTurn(sender, e) End If End Sub Everything works smoothly, except i'm trying to make it seem like the computer has to "think" before making its move. So what i've tried to do is place a System.Threading.Sleep() call in different places in the code above. The problem is that instead of making the computer look like its thinking, the program waits and then puts the X and O together at the same time. Can someone help me make it so that the program puts an X wherever i click AND THEN wait before it places an O? Edit: in case any of you are wondering, i realize that the computers AI is ridiculously dumb, but its just to mess around right now. Later on i will implement a serious AI..hopefully.

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  • Excel process not ending in Cluster environment

    - by Vasanth
    When we try to close excel object, it fails to close to cluster environment. The same is working fine in QA and UAT environment. public bool KillExcelProcess() { try { object misValue = System.Reflection.Missing.Value; wbObj.Save(); wbObj.Close(true, misValue, misValue); appC.Workbooks.Close(); appC.Quit(); System.Runtime.InteropServices.Marshal.ReleaseComObject(objSheet); System.Runtime.InteropServices.Marshal.ReleaseComObject(wbObj); System.Runtime.InteropServices.Marshal.ReleaseComObject(appC); wbObj = null; appC = null; } catch (Exception ex) { //throw ex; } finally { System.Threading.Thread.Sleep(5000); GC.Collect(); } return true; Calling function #endregion try { log.Info("CloseExcelService (MeasureSavingsComputeBO) Starts ..."); exConverter.KillExcelProcess(); while (true) { try { File.Delete(strFilename); break; } catch (Exception ex) { } }

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  • ASP.NET MVC 2 - How do I use an Interface as the Type for a Strongly Typed View

    - by Rake36
    I'd like to keep my concrete classes separate from my views. Without using strongly typed views, I'm fine. I just use a big parameter list in the controller method signatures and then use my service layer factory methods to create my concrete objects. This is actually just fine with me, but it got me thinking and after a little playing, I realized it was literally impossible for a controller method to accept an interface as a method parameter - because it has no way of instantiating it. Can't create a strongly-typed view using an interface through the IDE either (which makes sense actually). So my question. Is there some way to tell the controller how to instantiate the interface parameter using my service layer factory methods? I'd like to convert from: [Authorize] [AcceptVerbs(HttpVerbs.Post)] [UrlRoute(Path = "Application/Edit/{id}")] public ActionResult Edit(String id, String TypeCode, String TimeCode, String[] SelectedSchoolSystems, String PositionChoice1, String PositionChoice2, String PositionChoice3, String Reason, String LocationPreference, String AvailableDate, String RecipientsNotSelected, String RecipientsSelected) { //New blank app IApplication _application = ApplicationService.GetById(id); to something like [Authorize] [AcceptVerbs(HttpVerbs.Post)] [UrlRoute(Path = "Application/Edit/{id}")] public ActionResult Edit(String id, IApplication app) { //Don't need to do this anymore //IApplication _application = ApplicationService.GetById(id);

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  • Prototypal inheritance should save memory, right?

    - by Techpriester
    Hi Folks, I've been wondering: Using prototypes in JavaScript should be more memory efficient than attaching every member of an object directly to it for the following reasons: The prototype is just one single object. The instances hold only references to their prototype. Versus: Every instance holds a copy of all the members and methods that are defined by the constructor. I started a little experiment with this: var TestObjectFat = function() { this.number = 42; this.text = randomString(1000); } var TestObjectThin = function() { this.number = 42; } TestObjectThin.prototype.text = randomString(1000); randomString(x) just produces a, well, random String of length x. I then instantiated the objects in large quantities like this: var arr = new Array(); for (var i = 0; i < 1000; i++) { arr.push(new TestObjectFat()); // or new TestObjectThin() } ... and checked the memory usage of the browser process (Google Chrome). I know, that's not very exact... However, in both cases the memory usage went up significantly as expected (about 30MB for TestObjectFat), but the prototype variant used not much less memory (about 26MB for TestObjectThin). I also checked: The TestObjectThin instances contain the same string in their "text" property, so they are really using the property of the prototype. Now, I'm not so sure what to think about this. The prototyping doesn't seem to be the big memory saver at all. I know that prototyping is a great idea for many other reasons, but I'm specifically concerned with memory usage here. Any explanations why the prototype variant uses almost the same amount of memory? Am I missing something?

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  • Is there a useDirtyFlag option for Tomcat 6 cluster configuration?

    - by kevinjansz
    In Tomcat 5.0.x you had the ability to set useDirtyFlag="false" to force replication of the session after every request rather than checking for set/removeAttribute calls. <Cluster className="org.apache.catalina.cluster.tcp.SimpleTcpCluster" managerClassName="org.apache.catalina.cluster.session.SimpleTcpReplicationManager" expireSessionsOnShutdown="false" **useDirtyFlag="false"** doClusterLog="true" clusterLogName="clusterLog"> ... The comments in the server.xml stated this may be used to make the following work: <% HashMap map = (HashMap)session.getAttribute("map"); map.put("key","value"); %> i.e. change the state of an object that has already been put in the session and you can be sure that this object still be replicated to the other nodes in the cluster. According to the Tomcat 6 documentation you only have two "Manager" options - DeltaManager & BackupManager ... neither of these seem to allow this option or anything like it. In my testing the default setup: <Cluster className="org.apache.catalina.ha.tcp.SimpleTcpCluster"/> where you get the DeltaManager by default, it's definitely behaving as useDirtyFlag="true" (as I'd expect). So my question is - is there an equivalent in Tomcat 6? Looking at the source I can see a manager implementation "org.apache.catalina.ha.session.SimpleTcpReplicationManager" which does have the useDirtyFlag but the javadoc comments in this state it's "Tomcat Session Replication for Tomcat 4.0" ... I don't know if this is ok to use - I'm guessing not as it's not mentioned in the main cluster configuration documentation.

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  • Unit testing code which uses Umbraco v4 API

    - by Jason Evans
    I'm trying to write a suite of integration tests, where I have custom code which uses the Umbraco API. The Umbraco database lives in a SQL Server CE 4.0 database (*.sdf file) and I've managed to get that association working fine. My problem looks to be dependancies in the Umbraco code. For example, I would like to create a new user for my tests, so I try: var user = User.MakeNew("developer", "developer", "mypassword", "[email protected]", adminUserType); Now as you can see, I have pass a user type which is an object. I've tried two separate ways to create the user type, both of which fail due to a null object exception: var adminUserType = UserType.GetUserType(1); var adminUserType2 = new UserType(1); The problem is that in each case the UserType code calls it's Cache method which uses the HttpRuntime class, which naturally is null. My question is this: Can someone suggest a way of writing integration tests against Umbraco code? Will I have to end up using a mocking framework such as TypeMock or JustMock?

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  • Copying a subset of data to an empty database with the same schema

    - by user193655
    I would like to export part of a database full of data to an empty database. Both databases has the same schema. I want to maintain referential integrity. To simplify my cases it is like this: MainTable has the following fields: 1) MainID integer PK 2) Description varchar(50) 3) ForeignKey integer FK to MainID of SecondaryTable SecondaryTable has the following fields: 4) MainID integer PK (referenced by (3)) 5) AnotherDescription varchar(50) The goal I'm trying to accomplish is "export all records from MainTable using a WHERE condition", for example all records where MainID < 100. To do it manually I shuold first export all data from SecondaryTable contained in this select: select * from SecondaryTable ST outer join PrimaryTable PT on ST.MainID=PT.MainID then export the needed records from MainTable: select * from MainTable where MainID < 100. This is manual, ok. Of course my case is much much much omre complex, I have 200+ tables, so donig it manually is painful/impossible, I have many cascading FKs. Is there a way to force the copy of main table only "enforcing referntial integrity". so that my query is something like: select * from MainTable where MainID < 100 WITH "COPYING ALL FK sources" In this cases also the field (5) will be copied. ====================================================== Is there a syntax or a tool to do this? Table per table I'd like to insert conditions (like MainID <100 is only for MainTable, but I have also other tables).

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  • C# Minimize all running windows when application runs

    - by Derek
    I am working on a C# windows form application. How can i edit my code in a way that when more than 2 faces is being detected by my webcam. More information: When "FaceDetectedLabel.Text = "Faces Detected : " + cam.facesdetected.ToString();" becomes Face Detected: 2 or more... How can i do the following: Minimize all program running except my application. Log out of my computer Here is my code: namespace PBD { public partial class MainPage : Form { //declaring global variables private Capture capture; //takes images from camera as image frames public MainPage() { InitializeComponent(); } private void ProcessFrame(object sender, EventArgs arg) { Wrapper cam = new Wrapper(); //show the image in the EmguCV ImageBox WebcamPictureBox.Image = cam.start_cam(capture).Resize(390, 243, Emgu.CV.CvEnum.INTER.CV_INTER_CUBIC).ToBitmap(); FaceDetectedLabel.Text = "Faces Detected : " + cam.facesdetected.ToString(); } private void MainPage_Load(object sender, EventArgs e) { #region if capture is not created, create it now if (capture == null) { try { capture = new Capture(); } catch (NullReferenceException excpt) { MessageBox.Show(excpt.Message); } } #endregion Application.Idle += ProcessFrame; }

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  • Using complex where clause in NHibernate mapping layer

    - by JLevett
    I've used where clauses previously in the mapping layer to prevent certain records from ever getting into my application at the lowest level possible. (Mainly to prevent having to re-write lots of lines of code to filter out the unwanted records) These have been simple, one column queries, like so this.Where("Invisible = 0"); However a scenario has appeared which requires the use of an exists sql query. exists (select ep_.Id from [Warehouse].[dbo].EventPart ep_ where Id = ep_.EventId and ep_.DataType = 4 In the above case I would usually reference the parent table Event with a short name, i.e. event_.Id however as Nhibernate generates these short names dynamically it's impossible to know what it's going to be. So instead I tried using just Id, from above ep_ where Id = ep_.EventId When the code is run, because of the dynamic short names the EventPart table short name ep_ is has another short name prefixed to it, event0_.ep_ where event0_ refers to the parent table. This causes an SQL error because of the . in between event0_ and ep_ So in my EventMap I have the following this.Where("(exists (select ep_.Id from [isnapshot.Warehouse].[dbo].EventPart ep_ where Id = ep_.EventId and ep_.DataType = 4)"); but when it's generated it creates this select cast(count(*) as INT) as col_0_0_ from [isnapshot.Warehouse].[dbo].Event event0_ where (exists (select ep_.Id from [isnapshot.Warehouse].[dbo].EventPart event0_.ep_ where event0_.Id = ep_.EventId and ep_.DataType = 4) It has correctly added the event0_ to the Id Was the mapping layer where clause built to handle this and if so where am I going wrong?

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  • Node & Redis: Crucial Design Issues in Production Mode

    - by Ali
    This question is a hybrid one, being both technical and system design related. I'm developing the backend of an application that will handle approx. 4K request per second. We are using Node.js being super fast and in terms of our database struction we are using MongoDB, with Redis being a layer between Node and MongoDB handling volatile operations. I'm quite stressed because we are expecting concurrent requests that we need to handle carefully and we are quite close to launch. However I do not believe I've applied the correct approach on redis. I have a class Student, and they constantly change stages(such as 'active', 'doing homework','in lesson' etc. Thus I created a Redis DB for each state. (1 for being 'active', 2 for being 'doing homework'). Above I have the structure of the 'active' students table; xa5p - JSON stringified object #1 pQrW - JSON stringified object #2 active_student_table - {{studentId:'xa5p'}, {studentId:'pQrW'}} Since there is no 'select all keys method' in Redis, I've been suggested to use a set such that when I run command 'smembers' I receive the keys and later on do 'get' for each id in order to find a specific user (lets say that age older than 15). I've been also suggested that in fact I used never use keys in production mode. My question is, no matter how 'conceptual' it is, what specific things I should avoid doing in Node & Redis in production stage?. Are they any issues related to my design? Students must be objects and I sure can list them in a list but I haven't done yet. Is it that crucial in production stage?

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