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WCF Web Service Binding

As of Q1 2009, RadMenu supports load on demand from WCF service.

The steps below show how to load the items of RadMenu from WCF service. It shows how to use the context object to pass information from the client to the OperationContract. We will set additional Attributes for every item (in addition to the Text and Value properties) so we can see how to use them in the OnClientItemPopulated event.

  1. Create a new Web Site in Visual Studio 2008. Make sure the target framework is set to 3.5

  2. Drag RadMenu from your toolbox. From the SmartTag click on the Add RadScriptManager link. It will automatically register the handler in the web.config file

RadMenu Add ScriptManager

RadMenu Added Handler

  1. Add the WCF service – right click on your project in the Solution Explorer and select Add New Item.

This is important: select the Ajax-enabled WCF service option (do not mix it with WCF Service):

RadMenu Adding WCF Service

Clicking the Add button will create the .svc file as well as the code behind file placed in the App_Code folder. The web.config file is also automatically updated with the appropriate system.serviceModel node:

<system.servicemodel>
  <behaviors>
    <endpointBehaviors>
      <behavior name="ServiceAspNetAjaxBehavior">
        <enableWebScript />
      </behavior>
    </endpointBehaviors>
  </behaviors>
  <serviceHostingEnvironment aspNetCompatibilityEnabled="true" />
  <services>
    <service name="Service">
      <endpoint address="" behaviorConfiguration="ServiceAspNetAjaxBehavior" binding="webHttpBinding" contract="Service" />
    </service>
  </services>
</system.servicemodel>

These settings are important . If you don't have them correct - you might receive a javascript error: Method "MethodName" Failed.

  1. Open the Service.cs file and add the method which will return the menu items.
[ServiceContract(Namespace = "")]
[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
public class Service
{
    [OperationContract]
    public RadMenuItemData[] GetData(RadMenuItemData item, IDictionary<string, object> context)
    {
        List<RadMenuItemData> items = new List<RadMenuItemData>();
        //use the context to get the selected radio button
        string productsSuite = context["ProductSuite"].ToString();
        //the datasource
        List<String> radControls = new List<string>()
                              {
                                  "RadMenu",
                                  "RadMenu",
                                  "RadTreeView",
                                  "RadToolBar"
                              };
        foreach (string radControl in radControls)
        {
            RadMenuItemData newItem = new RadMenuItemData()
            {
                Text = string.Format("{0} for {1}", radControl, productsSuite),
                Value = radControl,
                ImageUrl = "Images/" + radControl + ".gif",
                //Optional: set the attribute of the item which will be used
                //in the OnClientNodePopulated event
                Attributes = new Dictionary<string, object> { { "MyCustomAttribute", radControl } }
            };
            items.Add(newItem);
        }
        return items.ToArray();
    }
} 

Note that the above code uses the context object which passes the information of the selected RadioButton on the page and is set in the OnClientItemPopulating event.

You can set additional attributes to every item by using the Attributes dictionary. Later, you can read these attributes in OnClientItemPopulated event.

function OnClientItemPopulatingHandler(sender, e) 
{        
    var context = e.get_context();
    //using jQuery to get the checked item and pass it to the server        
    context["ProductSuite"] = $telerik.$("input[name='rblSuites']:checked").val();
}       

function OnClientItemPopulatedHandler(sender, e)
{        
    var items = e.get_item().get_items();
    for (var i = 0; i < items.get_count(); i++)
    {           
        var item = items.getItem(i);
        //getting the attribute of the item  
        var myCustomAttribute = item.get_attributes().getAttribute("MyCustomAttribute");
        //do something with the attribute
    }    
}

Here is the menu declaration:

<asp:RadioButtonList ID="rblSuites" runat="server">
    <asp:ListItem Selected="True">ASP.NET AJAX</asp:ListItem>
    <asp:ListItem>WPF</asp:ListItem>
    <asp:ListItem>Silverlight</asp:ListItem>
    <asp:ListItem>Winforms</asp:ListItem>
</asp:RadioButtonList>
<telerik:RadMenu RenderMode="Lightweight" ID="RadMenu1" OnClientItemPopulating="OnClientItemPopulatingHandler"
    OnClientItemPopulated="OnClientItemPopulatedHandler" runat="server">
    <Items>
        <telerik:RadMenuItem Text="Products" ExpandMode="WebService">
        </telerik:RadMenuItem>
    </Items>
    <WebServiceSettings Method="GetData" Path="Service.svc" />
</telerik:RadMenu>

and the result:

RadMenu WCF Service Result

See Also

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