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  • WebClient DownloadStringCompleted Never Fired in Console Application

    - by azamsharp
    I am not sure why the callback methods are not fired AT ALL. I am using VS 2010. static void Main(string[] args) { try { var url = "some link to RSS FEED"; var client = new WebClient(); client.DownloadStringCompleted += new DownloadStringCompletedEventHandler(client_DownloadStringCompleted); client.DownloadDataCompleted += new DownloadDataCompletedEventHandler(client_DownloadDataCompleted); client.DownloadStringAsync(new Uri(url)); } catch (Exception ex) { Console.WriteLine(ex.Message); } } // THIS IS NEVER FIRED static void client_DownloadDataCompleted(object sender, DownloadDataCompletedEventArgs e) { Console.WriteLine("something"); } // THIS IS NEVER FIRED static void client_DownloadStringCompleted(object sender, DownloadStringCompletedEventArgs e) { Console.WriteLine("do something"); var rss = XElement.Parse(e.Result); var pictures = from item in rss.Descendants("channel") select new Picture { Name = item.Element("title").Value }; foreach (var picture in pictures) { Console.WriteLine(picture.Name); Console.WriteLine(picture.Url); } }

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  • C# generic list <T> how to get the type of T?

    - by Daok
    Hello, Let say I have a List< T > abc = new List< T >; inside a class public class MyClass<T>//.... Later, when I initialize the class the T because MyTypeObject1. So I have a generic list of List< MyTypeObject1 >. I would like to know, what type of object the list of my class contain. Example, the list called abc contain what type of object? I cannot do abc[0].GetType(); because the list might contain 0 element. How can I do it?

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  • Error loading contents from a XML file into a dropdownlist

    - by Chaitanya
    private void BindCountry() { XmlDocument doc = new XmlDocument(); doc.Load(Server.MapPath("countries.xml")); foreach (XmlNode node in doc.SelectNodes("//country")) { usrlocationddl.Items.Add(new ListItem(node.InnerText, node.Attributes["codes"].InnerText)); //ddlCountry.Items.Add(new ListItem(node.InnerText, node.Attributes["code"].InnerText)); } } The above code am using for loading countries List from an xml file into a dropdown list. But while doing so am encountering a Null Reference error. Object reference not set to an instance of an object. Where in the code should I be changing, so that I can escape the error.

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  • Validate cyclic organization unit

    - by abmv
    I have a object Organization Unit and I have a self reference to it in the same object public class OrganizationUnit: IOrganizationUnit { private string fName; public string Name { get { return fName; } set { SetPropertyValue("Name", ref fName, (string) value); } } private OrganizationUnit fManagedBy; public IOrganizationUnit ManagedBy { get { return fManagedBy; } set { SetPropertyValue("ManagedBy", ref fManagedBy, (OrganizationUnit)value); } } } I need a method that will throw an exception if it finds a child organization unit in the third level is referencing a parent Organization unit, or to say cyclic parent organization. A is main B managed by A C

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  • How to invoke client ActiveX via javascript

    - by Captain Kidd
    Hi I want to let server to invoke client ActiveX via javascript. The script work well as it run on my local system. Then I place it into Apache Server and it's malfunction. Script: <object id="lv_obj" classid = "CLSID:30A92485-94D2-4CBA-AC32-EF276B7F777B" CODEBASE="" ></OBJECT> try { document.all.lv_obj.Init("PCS_Tes"); } catch (err) { window.alert("????: " + err.message); } I guess the reason is script on server can't invoke user client ActiveX. If I need config something on Apache?

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  • Lazy-loading flash objects

    - by friedo
    I'm using the jQuery lazy-loading plugin to defer loading of below-the-fold images on a large web page. This works great. Now, I would like to apply the same technique to a large Flash object which is also below-the-fold. I don't think the lazy-load plugin handles things that aren't images (at least it doesn't look that way so far.) I may have to do it myself. In that case, how do I detect when the area containing the Flash object becomes visible?

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  • 640 enterprise library caching threads - how?

    - by JohnW
    We have an application that is undergoing performance testing. Today, I decided to take a dump of w3wp & load it in windbg to see what is going on underneath the covers. Imagine my surprise when I ran !threads and saw that there are 640 background threads, almost all of which seem to say the following: OS Thread Id: 0x1c38 (651) Child-SP RetAddr Call Site 0000000023a9d290 000007ff002320e2 Microsoft.Practices.EnterpriseLibrary.Caching.ProducerConsumerQueue.WaitUntilInterrupted() 0000000023a9d2d0 000007ff00231f7e Microsoft.Practices.EnterpriseLibrary.Caching.ProducerConsumerQueue.Dequeue() 0000000023a9d330 000007fef727c978 Microsoft.Practices.EnterpriseLibrary.Caching.BackgroundScheduler.QueueReader() 0000000023a9d380 000007fef9001552 System.Threading.ExecutionContext.runTryCode(System.Object) 0000000023a9dc30 000007fef72f95fd System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object) 0000000023a9dc80 000007fef9001552 System.Threading.ThreadHelper.ThreadStart() If i had to give a guess, I'm thinkign that one of these threads are getting spawned for each run of our app - we have 2 app servers, 20 concurrent users, and ran the test approximately 30 times...it's in the neighborhood. Is this 'expected behavior', or perhaps have we implemented something improperly? The test ran hours ago, so i would have expected any timeouts to have occurred already.

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  • (VB.NET + WPF) Drag + Drop (to allow user sorting) of stackpanel elements within a Scrollviewer?

    - by Matt H.
    I have good model (I think!) for how to allow a user to drag an element in a stackpanel and reposition it to another location within the stackpanel. However, my Stackpanel is placed within a ScrollViewer, like this (generalized): <ScrollViewer> <StackPanel> ....First item ....Second item ....Third item ....Etc. </StackPanel> <ScrollViewer> Here is the problem, I wish to simulate the functionality of programs like word, where if I am dragging selected content (or an object) outside the viewable area, the window will scroll in the direction of the mouse to see more places to drop my nifty little object. ...i.e. If I move the mouse to the top of my ScrollViewer while dragging a stackpanel's contents, I want the scrollviewer to slowly move up so I can see more locations to drop my content. Any suggestions? If you can help me solve this, you will be a godsend!

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  • Why does DataSet.HasChanges() return true if called in the same function as change but false otherwi

    - by Chapso
    Assuming that the buttons are being clicked in order, the following code modifies row 1 in a .net DataSet, then row 0. HasChanges returns true, but GetChanges only gives me the change for row 0. If I comment out the line in the button2 click event that modifies row 0, then HasChanges returns false. Can anyone explain to me why HasChanges() and GetChanges() only return true when they are called in the same function as the change to the DataSet? Protected Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click __ds1.Tables(0).Rows(1)("EmployeeName") = "TestStuff" End Sub Protected Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click __ds1.Tables(0).Rows(0)("EmployeeName") = "TestStuff" If __ds1.HasChanges(DataRowState.Modified Or DataRowState.Added) Then __ds2 = __ds1.GetChanges(DataRowState.Modified _ Or DataRowState.Added) GridView3.DataSource = __ds2.Tables("Users").DefaultView GridView3.DataBind() Else End If End Sub

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  • Scala type conversion error, need help!

    - by Mansoor Ashraf
    Hello I am getting a weird error when trying to use a Java map in Scala. This is the snippet of code val value:Double = map.get(name) if (value eq null) map.put(name, time) else map.put(name, value + time) the map is defined as val map=new ConcurrentHashMap[String,Double] and this is the error I am getting error: type mismatch; found : Double required: ?{val eq: ?} Note that implicit conversions are not applicable because they are ambiguous: both method double2Double in object Predef of type (Double)java.lang.Double and method doubleWrapper in object Predef of type (Double)scala.runtime.RichDouble are possible conversion functions from Double to ?{val eq: ?} if (value eq null) map.put(name, time) I am new to Scala so I am having a hard time parsing the stacktrace. Any help would be appreciated

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  • Setting HTML Text Element value

    - by Gpx
    Hi, in my C# WPF prog i´am trying to set a value of a HTML Text Element which is defined like: <input name="tbBName" type="text" id="tbBName" tabindex="1" /> What i found about it and tried is: mshtml.HTMLDocument doc = (mshtml.HTMLDocument)webBrowser1.Document; mshtml.HTMLInputTextElement tbName = (mshtml.HTMLInputTextElement)doc.getElementsByName("tbBName"); tbName.value = "Test"; But i got the exception: Unable to cast COM object of type 'System.__ComObject' to interface type 'mshtml.HTMLInputTextElement'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{3050F520-98B5-11CF-BB82-00AA00BDCE0B}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE)). I know what it says but i dont know which object i can use to access the Texbox. Thanks for any answers.

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  • SQLDependency thread

    - by user171523
    i am in the process implementing SQLdepenency i would like to know in case of Dependency Handler exeuctues will it spun a different thred from main Process ? What will happen when the event handler triggers? Do i need to worry about any multithreds issues? public void CreateSqlDependency() { try { using (SqlConnection connection = (SqlConnection)DBFactory.GetDBFactoryConnection(Constants.SQL_PROVIDER_NAME)) { SqlCommand command = (SqlCommand)DBFactory.GetCommand(Constants.SQL_PROVIDER_NAME); command.CommandText = watchQuery; command.CommandType = CommandType.Text; SqlDependency dependency = new SqlDependency(command); //Create the callback object dependency.OnChange += new OnChangeEventHandler(this.QueueChangeNotificationHandler); SqlDependency.Start(connectionString); DataTable dataTable = DBFactory.ExecuteSPReDT(command); } } catch (SqlException sqlExp) { throw sqlExp; } catch (Exception ex) { throw ex; } } public void QueueChangeNotificationHandler(object caller, SqlNotificationEventArgs e) { if(e.Info == SqlNotificationInfo.Insert) Fire(); }

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  • Client Side Includes on HTML pages

    - by Roy Rico
    Previously I had thought that there were only ways to get content from external URLs into your page. These 2 ways are use an IFRAME or Javascript to include it into your pages. I've just learned of a new way using the tag. <object type="text/html" frameborder="0" data="http://Server/URL/"></object> I have found some content online that confirms this ability, but it doesn't talk much about features such as Accessibility and SEO of the page. Does anyone have any experience with this? Is there any information available regarding using this method and how it effects Accessibility and SEO?

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  • Rewriting VB.NET Lambda experession as a C# statement

    - by ChadD
    I downgraded my app from version 4 of the framework to version 4 and now I want to implement this VB.NET lambda function statement (which works on 3.5) Dim colLambda As ColumnItemValueAccessor = Function(rowItem As Object) General_ItemValueAccessor(rowItem, colName) and rewrite it in C#. This was my attempt: ColumnItemValueAccessor colLambda = (object rowItem) => General_ItemValueAccessor(rowItem, colName); When I did this, I get the following error: Error 14 One or more types required to compile a dynamic expression cannot be found. Are you missing references to Microsoft.CSharp.dll and System.Core.dll? C:\Source\DotNet\SqlSmoke\SqlSmoke\UserControls\ScriptUserControl.cs 84 73 SqlSmoke However, when I downgraded the app from version 4.0 of the framework to 3.5 (because our users only hae 3.5 and don't have rights to install 4.0). when I did this, the reference to "Microsoft.CSharp" was broken. Can I rewrite the VB.NET command in C# using syntax that is valid in C# 3.5 as I was able to in VB.NET? What would the syntax be?

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  • PHP array : simple question about multidimensional array

    - by Tristan
    Hello, i've got a SQL query which returns multiple rows, and i have : $data = array( "nom" => $row['nom'] , "prix" => $row['rapport'], "average" => "$moyenne_ge" ); which is perfect, but only if my query returns one row. i tried that : $data = array(); $data[$row['nom']]["nom"] = $row['nom'] ; ... $data[$row['nom']]['average'] = "$moyenne_ge"; in order to have : $data[brand1][nom] = brand1 $data[brand1][average] = 150$ $data[brand2][nom] = brand2 $data[brand2][average] = 20$ ... but when i do : json_encode($data) i only have the latest JSON object instead of all JSON object from my request as if my array has only one brand instead of 10. I guess i did something stupid somewhere. Thanks for your help

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  • Winforms Hotkey, Help?

    - by Di4g0n4leye
    namespace WebBrowser { public partial class MainForm : Form { public MainForm() { InitializeComponent(); } int GetPixel(int x, int y) { Bitmap bmp = new Bitmap(1, 1, PixelFormat.Format32bppPArgb); Graphics grp = Graphics.FromImage(bmp); grp.CopyFromScreen(new Point(x,y), Point.Empty, new Size(1,1)); grp.Save(); return bmp.GetPixel(0, 0).ToArgb(); } void Button1Click(object sender, EventArgs e) { int x = Cursor.Position.X; int y = Cursor.Position.Y; int pixel = GetPixel(x,y); textBox1.Text = pixel.ToString(); } void MainFormLoad(object sender, EventArgs e) { webBrowser1.Navigate("http://google.com"); } } } } i want to add a hotkey that call Button1 on Press, How can that be done?

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  • jQuery won't parse my JSON from AJAX query

    - by littlecharva
    Hi, I'm having difficulty parsing some JSON data returned from my server using jQuery.ajax() To perform the AJAX I'm using: $.ajax({ url: myUrl, cache: false, dataType: "json", success: function(data){ ... }, error: function(e, xhr){ ... } }); And if I return an array of items then it works fine: [ { title: "One", key: "1" }, { title: "Two", key: "2" } ] The success function is called and receives the correct object. However, when I'm trying to return a single object: { title: "One", key: "1" } The error function is called and xhr contains 'parsererror'. I've tried wrapping the JSON in parenthesis on the server before sending it down the wire, but it makes no difference. Yet if I paste the content into a string in Javascript and then use the eval() function, it evaluates it perfectly. Any ideas what I'm doing wrong? Anthony

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  • LINQ query checks for null

    - by user300992
    I have a userList, some users don't have a name (null). If I run the first LINQ query, I got an error saying "object reference not set to an instance of an object" error. var temp = (from a in userList where ((a.name == "john") && (a.name != null)) select a).ToList(); However, if I switch the order by putting the checking for null in front, then it works without throwing any error: var temp = (from a in userList where ((a.name != null) && (a.name == "john")) select a).ToList(); Why is that? If that's pure C# code (not LINQ), I think both would be the same. I don't have SQL profiler, I am just curious what will be the difference when they are being translated on SQL level.

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  • CheckBox ListView SelectedValues DependencyProperty Binding

    - by Ristogod
    I am writing a custom control that is a ListView that has a CheckBox on each item in the ListView to indicate that item is Selected. I was able to do so with the following XAML. <ListView x:Class="CheckedListViewSample.CheckBoxListView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d"> <ListView.Style> <Style TargetType="{x:Type ListView}"> <Setter Property="SelectionMode" Value="Multiple" /> <Style.Resources> <Style TargetType="ListViewItem"> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="ListViewItem"> <Border BorderThickness="{TemplateBinding Border.BorderThickness}" Padding="{TemplateBinding Control.Padding}" BorderBrush="{TemplateBinding Border.BorderBrush}" Background="{TemplateBinding Panel.Background}" SnapsToDevicePixels="True"> <CheckBox IsChecked="{Binding IsSelected, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListViewItem}}}"> <CheckBox.Content> <ContentPresenter Content="{TemplateBinding ContentControl.Content}" ContentTemplate="{TemplateBinding ContentControl.ContentTemplate}" HorizontalAlignment="{TemplateBinding Control.HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding Control.VerticalContentAlignment}" SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}" /> </CheckBox.Content> </CheckBox> </Border> </ControlTemplate> </Setter.Value> </Setter> </Style> </Style.Resources> </Style> </ListView.Style> </ListView> I however am trying to attempt one more feature. The ListView has a SelectedItems DependencyProperty that returns a collection of the Items that are checked. However, I need to implement a SelectedValues DependencyProperty. I also am implementing a SelectedValuesPath DependencyProperty. By using the SelectedValuesPath, I indicate the path where the values are found for each selected item. So if my items have an ID property, I can specify using the SelectedValuesPath property "ID". The SelectedValues property would then return a collection of ID values. I have this working also using this code in the code-behind: using System.Windows; using System.Windows.Controls; using System.ComponentModel; using System.Collections; using System.Collections.Generic; namespace CheckedListViewSample { /// <summary> /// Interaction logic for CheckBoxListView.xaml /// </summary> public partial class CheckBoxListView : ListView { public static DependencyProperty SelectedValuesPathProperty = DependencyProperty.Register("SelectedValuesPath", typeof(string), typeof(CheckBoxListView), new PropertyMetadata(string.Empty, null)); public static DependencyProperty SelectedValuesProperty = DependencyProperty.Register("SelectedValues", typeof(IList), typeof(CheckBoxListView), new PropertyMetadata(new List<object>(), null)); [Category("Appearance")] [Localizability(LocalizationCategory.NeverLocalize)] [Bindable(true)] public string SelectedValuesPath { get { return ((string)(base.GetValue(CheckBoxListView.SelectedValuesPathProperty))); } set { base.SetValue(CheckBoxListView.SelectedValuesPathProperty, value); } } [Bindable(true)] [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)] [Category("Appearance")] public IList SelectedValues { get { return ((IList)(base.GetValue(CheckBoxListView.SelectedValuesPathProperty))); } set { base.SetValue(CheckBoxListView.SelectedValuesPathProperty, value); } } public CheckBoxListView() : base() { InitializeComponent(); base.SelectionChanged += new SelectionChangedEventHandler(CheckBoxListView_SelectionChanged); } private void CheckBoxListView_SelectionChanged(object sender, SelectionChangedEventArgs e) { List<object> values = new List<object>(); foreach (var item in SelectedItems) { if (string.IsNullOrWhiteSpace(SelectedValuesPath)) { values.Add(item); } else { try { values.Add(item.GetType().GetProperty(SelectedValuesPath).GetValue(item, null)); } catch { } } } base.SetValue(CheckBoxListView.SelectedValuesProperty, values); e.Handled = true; } } } My problem is that my binding only works one way right now. I'm having trouble trying to figure out how to implement my SelectedValues DependencyProperty so that I could Bind a Collection of values to it, and when the control is loaded, the CheckBoxes are checked with items that have values that correspond to the SelectedValues. I've considered using the PropertyChangedCallBack event, but can't quite figure out how I could write that to achieve my goal. I'm also unsure of how I find the correct ListViewItem to set it as Selected. And lastly, if I can find the ListViewItem and set it to be Selected, won't that fire my SelectionChanged event each time I set a ListViewItem to be Selected?

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  • How to add a view helper directory (zend framework)

    - by Cédric Girard
    Hi, I begin with ZF (1.9.7), and I want to use View Helpers from a library shared between all my projects. But I can't find how to add it directory to the helpers path. My herpers works fines when I put them in application's helpers path. Here is the error, where I find the path to ZF helpers, and path to the applications ones. object(ArrayObject)#71 (3) { ["exception"]=> object(Zend_Loader_PluginLoader_Exception)#70 (6) { ["message:protected"]=> string(151) "Plugin by name 'Voo' was not found in the registry; used paths: Zend_View_Helper_: Zend/View/Helper/;C:/ZendStd/www/applis/VOO4_PROJECTX/views\helpers/" ["string:private"]=> string(0) "" ["code:protected"]=> int(0) ["file:protected"]=> string(89) "C:\Program Files\Zend\ZendServer\share\ZendFramework\library\Zend\Loader\PluginLoader.php" ["line:protected"]=> int(401) Best regards Cédric

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  • prevent bots to query my database several times

    - by Alain
    Hi all, I'm building an application that is a kind of registry. Think about the dictionary: you lookup for a word and it return something if the word is founded. Now, that registry is going to store valuable informations about companies, and some could be tempted to get the complete listing. My application use EJB 3.0 that replies to WS. So I was thinking about permits a maximum of 10 query per IP address per day. Storing the IP address and a counter on a table that would be empty by a script every night. Is it a good idea/practice to do so? If yes, how can I get the IP address on the EJB side? Is there a better way to prevent something to get all the data from my database? I've also though about CAPTCHA but I think it's a pain for the user, and sometime, they are difficult to read even for real human. Hope it's all clear since I'm not english... Thanks Alain

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  • Selecting data from SQL Server table according to Month

    - by MarceloRamires
    I have to come up with a way to get data from a SQL server table given it's month There's a smalldatetime type field called "date" in the "events" table and a field from it looks like this: 29/01/2003 17:00:00 It should be one among those that appear in the gridview when I select jan/03 in a given DropDownList control in ASP.NET. What would be the best way to do this? Assuming I only want to go as long as 10 years to the past, wouldn't making a dictionary be a good way? How do I change it so the top month is always the current, and each month another options appeaars in the dropdown ? It should be a common issue, so that shall not be a trick, but I want a good and clean way of doing this, and (since I'm new to asp.net) I myself would come up with something messy after a long time trying. So what I want is: -Select -Best way of populating DropDownList (with the current month always at the top) -Best way to bind the DropDownList user-friendly way of writing months to the select query-friendly way of writing datetimes Info: ASP.NET, (C# or VB.NET), SQL Server 2005

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  • Bind listbox in WPF with grouping

    - by Michael Stoll
    Hi, I've got a collection of ViewModels and want to bind a ListBox to them. Doing some investigation I found this. So my ViewModel look like this (Pseudo Code) interface IItemViewModel { string DisplayName { get; } } class AViewModel : IItemViewModel { string DisplayName { return "foo"; } } class BViewModel : IItemViewModel { string DisplayName { return "foo"; } } class ParentViewModel { IEnumerable<IItemViewModel> Items { get { return new IItemViewModel[] { new AItemViewModel(), new BItemViewModel() } } } } class GroupViewModel { static readonly GroupViewModel GroupA = new GroupViewModel(0); static readonly GroupViewModel GroupB = new GroupViewModel(1); int GroupIndex; GroupViewModel(int groupIndex) { this.GroupIndex = groupIndex; } string DisplayName { get { return "This is group " + GroupIndex.ToString(); } } } class ItemGroupTypeConverter : IValueConverter { object Convert(object value, Type targetType, object parameter, CultureInfo culture) { if (value is AItemViewModel) return GroupViewModel.GroupA; else return GroupViewModel.GroupB; } } And this XAML <UserControl.Resources> <vm:ItemsGroupTypeConverter x:Key="ItemsGroupTypeConverter "/> <CollectionViewSource x:Key="GroupedItems" Source="{Binding Items}"> <CollectionViewSource.GroupDescriptions> <PropertyGroupDescription Converter="{StaticResource ItemsGroupTypeConverter }"/> </CollectionViewSource.GroupDescriptions> </CollectionViewSource> </UserControl.Resources> <ListBox ItemsSource="{Binding Source={StaticResource GroupedItems}}"> <ListBox.GroupStyle> <GroupStyle> <GroupStyle.HeaderTemplate> <DataTemplate> <TextBlock Text="{Binding DisplayName}" FontWeight="bold" /> </DataTemplate> </GroupStyle.HeaderTemplate> </GroupStyle> </ListBox.GroupStyle> <ListBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding DisplayName}" /> </DataTemplate> </ListBox.ItemTemplate> </ListBox> This works somehow, exept of the fact that the binding of the HeaderTemplate does not work. Anyhow I'd prefer omitting the TypeConverter and the CollectionViewSource. Isn't there a way to use a property of the ViewModel for Grouping? I know that in this sample scenario it would be easy to replace the GroupViewModel with a string an have it working, but that's not an option. So how can I bind the HeaderTemplate to the GroupViewModel?

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  • Instantiating a context in LINQ to Entities

    - by Jagd
    I've seen two different manners that programmers approach when creating an entity context in their code. The first is like such, and you can find it all over the MSDN code examples: public void DoSomething() { using TaxableEducationEntities context = new TaxableEducationEntities()) { // business logic and whatever else } } The second is to create the context as a private attribute in some class that encapsulates your business logic. So you would have something like: public class Education_LINQ { private TaxableEducationEntities context = new TaxableEducationEntities(); public void DoSomething() { var result = from a in context.luAction select a; // business logic and whatever else } } Which way is more efficient? Assume that you have two methods, one called DoSomething1() and another called DoSomething2(), and both methods incorporate the using statement to open the context and do whatever with it. Were you to call one method after the other, would there be any superfluous overhead going on, since essentially both methods create the context and then clean it up when they're done? As opposed to having just one private attribute that is created when a class object is instantiated, and then in turn cleaned up when the object goes out of scope?

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  • Why does python use 'magic methods'?

    - by Greg Beech
    I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available an object implements a method def __len__(self) and then it is called when you write len(obj). I was just wondering why objects don't simply define a len(self) method and have it called directly as a member of the object, e.g. obj.len()? I'm sure there must be good reasons for Python doing it the way it does, but as a newbie I haven't worked out what they are yet.

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