Showing posts with label Silverlight 4.0. Show all posts
Showing posts with label Silverlight 4.0. Show all posts

Thursday, August 25, 2011

How to Close the Browser Window from a Silverlight Application

All secured sites ask you to close your browser window after you sign out from a web application. This is a security measure which actually removes all session details from the browser cache.

If you are developing a secured site and want to close the browser window just after the user logs out from the application, this small tip will help you. If you want to develop the same behavior in your Silverlight application, this is how we can do the trick.

Use  the "System.Windows.Browser.HtmlPage.Window.Invoke()" method to call the Close() method of the browser window, as shown in the below code snippet:

private void OnWindowCloseClick(object sender, RoutedEventArgs e)

The above code when called will close the browser window where your Silverlight application is hosted. If it is a tab, it will close the Window tab instead. If you are using it inside Internet Explorer, it will ask you whether you really want to close the browser. If you press "No", it will remain in that page, and clicking "Yes" will close the browser tab/window

Wednesday, May 18, 2011

How to add a ServiceThrottlingBehavior to a WCF Service?

When working with WCF especially when middle-tier client applications uses Windows Communication Foundation, you should always think about performance and take some major design decisions and tuning parameters.

By adding ServiceThrottlingbehavior in web.config we can achieve high performance using WCF. Below is the sample serivceThrottleconfiguration settings in web.config in .NET 4.0 Framework.

        <behavior name="CommonService">
          <serviceMetadata httpGetEnabled="true" />
          <serviceDebug includeExceptionDetailInFaults="false" />
          <dataContractSerializer maxItemsInObjectGraph="2147483647" />
          <serviceThrottling maxConcurrentCalls="16" 
                             maxConcurrentSessions="100"   />

The main purpose for the throttling settings can be classified into the following two aspects:

  1. Controlled resource usage: With the throttling of concurrent execution, the usage of resources such as memory or threads can be limited to a reasonable level so that the system works well without hitting reliability issues.

  2. Balanced performance load: Systems always work in a balanced way when the load is controlled. If there are too much concurrent execution happening, a lot of contention and bookkeeping would happen and thus it would hurt the performance of the system.

In WCF 4, the default values of these settings are revised so that people don’t have to change the defaults in most cases. Here are the main changes:

  • MaxConcurrentSessions: default is 100 * ProcessorCount

  • MaxConcurrentCalls: default is 16 * ProcessorCount

  • MaxConcurrentInstances: default is the total of the above two, which follows the same pattern as before.

“ProcessorCount” is used as multiplier for the settings. So on a 4-proc server, you would get the default of MaxConcurrentCalls as 16 * 4 = 64. Thus the consideration is that, when you write a WCF service and you use the default settings, the service can be deployed to any system from low-end one-proc server to high-end such as 24-way server without having to change the settings. So CPU uses count as the multiplier.

Please note, these changes are for the default settings only. If you explicitly set these settings in either configuration or in code, the system would use the settings that you provided. No “ProcessCount” multiplier would be applied.

Thursday, December 30, 2010

Silverlight Programming: RadComboBox Virtualization

Telerik RadControls' API gives you the ability to configure the RadComboBox to support virtualization, which reduces the memory footprint of the application and speeds up the loading time thus enhancing additionally the UI performance. Some times its required to load thousands of items in a RadComboBox. By default the control creates RadComboBoxItem containers for each data item, so it might take some time to open the drop-down. To resolve the problem you just have to change the RadComboBox's ItemsPanel with VirtualizingStackPanel:

Here is the snippet of code block

<telerik:RadComboBox HorizontalAlignment="Left" TextSearchMode="StartsWith"
IsFilteringEnabled="True" OpenDropDownOnFocus="True" Width="200" 
IsEditable="True" IsDropDownOpen="False" Name="AccountDropDownList" 
SelectedValuePath="customer_number" DisplayMemberPath="customer_name" >
        <VirtualizingStackPanel />

Hope this is useful Nerd smile

Monday, December 20, 2010

WCF OperationContractAttribute with example

The OperationContractAttribute, also defined in the System.ServiceModel namespace, can be applied only to methods. It should declare to the method which belongs to a Service contract. Operation contract can be declared with below named parameters that provide control over the service description and message formats.

Name Specifies a different name for the operation instead of using the default, which is the method name.Action Controls the action header for messages to this operation.

ReplyAction Controls the action header for response messages from this operation.

IsOneWay Indicates whether the operation is one-way and has no reply. When operations are one-way, ReplyAction is not supported.

ProtectionLevel Enables the Service contract to specify constraints on how messages to
all operations in the contract are protected on the wire, that is, whether they are signed and encrypted.

IsInitiating Indicates whether invoking the operation initiates a new session between the caller and the service.

IsTerminating Indicates whether invoking the operation terminates an existing session between the caller and the service

Here is Sample WCF Class for reference.

// C#
[ServiceContract(Namespace = "")]
public class CrudContract
    [OperationContract(IsOneWay = true, Action = "urn:crud:insert")]
    void ProcessInsertMessage(Message message);
    [OperationContract(IsOneWay = true, Action = "urn:crud:update")]
    void ProcessUpdateMessage(Message message);
    [OperationContract(IsOneWay = true, Action = "urn:crud:delete")]
    void ProcessDeleteMessage(Message message);
    // The catch-all operation:
    [OperationContract(IsOneWay = true, Action = "*")]
    void ProcessUnrecognizedMessage(Message message);

Hope this is useful Party smile

Wednesday, December 15, 2010

“CleanRiaClientFilesTask" task failed unexpectedly

Recently few of our developers and me got this error while building my Silverlight application. I got this error while checking in the code and merge my code changes.

Error Details.

Error    38    The "CleanRiaClientFilesTask" task failed unexpectedly.
System.ArgumentException: Illegal characters in path.

To resolve this we need to do two simple steps.

Step 1: Go to this location in your system or your Framework install directory, for me its C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files. Clean all the temporary files under this location and leave the root folder empty.

Step 2: Go to your project location and Delete all the files in \obj folder. Basically all the files are stored in the \obj folder created by ria services.

Now clean the project and try building again. It worked for me. Hope this will help you. Good luck Hot smile

Thursday, December 09, 2010

Iterating through Generic List in C#

Recently I need to loop through a Generic list and bind the result to a Combobox. Here is how you can do this in C#

List<CCDSDateResult> list = new List<CCDSDateResult>();
for (int i = 0; i < e.Result.Count; i++)
    if (e.Result.ToList()[i].ccds_date.ToString().Length > 0)
        // Write your add item in the list
        list.Add(new CCDSDateResult(DateTime.Parse(e.Result.ToList()[i].ccds_date.ToString())));
// adding a empty record to the list
list.Insert(0, new CCDSDateResult());
this.OrderComboBox.ItemsSource = list.ToList();

Hope this is useful. Thumbs up

Friday, November 19, 2010

How Do I Set Textbox Focus in Silverlight4.0?

Here is an example to set focus for a text box in Silverlight application.

In Page.xaml

<UserControl x:Class="TextboxFocusTest.Page"
    Width="400" Height="300">
    <Grid x:Name="LayoutRoot" Background="White">        
        <StackPanel Width="150" VerticalAlignment="Center">            
            <TextBox x:Name="UserNameTextBox" IsTabStop="True" />    

In Page.xaml.cs

using System.Windows;
using System.Windows.Controls;
namespace TextboxFocusTest
    public partial class Page : UserControl
        public Page()
        private void UserControl_Loaded(object sender, RoutedEventArgs e)

Happy Coding..Smile