The server method 'LoadNodes' failed

[Wouter]

Hi,

When I tried to expand my nodes in my RadTreeView I get the following error: 'The server method 'LoadNodes' failed'

I've placed a RadTreeView on a UserControl, in the Page_Init the UserControl is initialized.

Control control = LoadControl("/Pages/Controls/MenuControl.ascx");
control.ID = "menuControl";
panelMenu.Controls.Add(control);

Now the RadTreeView is defined as following:

<telerik:RadTreeView ID="radTOC" runat="server" Width="250px" Visible="false" CssClass="RadTreeView_RadSkins"
    EnableEmbeddedSkins="False" ShowLineImages="false" Style="white-space: normal;">
    <WebServiceSettings Path="../../Services/TreeViewService.asmx" Method="LoadNodes" />
</telerik:RadTreeView>

The treenodes are added to the RadTreeView as following:

foreach (Publication sub in subPublications)
{
   RadTreeNode treeNode = new RadTreeNode(sub.Name, sub.PublicationID.ToString());
   treeNode.ExpandMode = TreeNodeExpandMode.WebService;
   radTOC.Nodes.Add(treeNode);
}

The webmethod in TreeViewService.asmx:

[System.Web.Script.Services.ScriptService]
public class TreeViewService : System.Web.Services.WebService
{
    [WebMethod]
    public static RadTreeNodeData[] LoadNodes(RadTreeNodeData node, object context)
    {
        List<RadTreeNodeData> result = new List<RadTreeNodeData>();
        RadTreeNodeData nodeData = new RadTreeNodeData();
        nodeData.Text = "Loaded on demand";
        nodeData.ExpandMode = TreeNodeExpandMode.WebService;
        result.Add(nodeData);
        return result.ToArray();
    }
}

Does anyone know what I'm doing wrong?

Regards,
Wouter splinter

[Nikolay Tsenkov]

Hi Wouter,

Could you, please, try using a tilde-noted relative path - my guess would be "~/Services/TreeViewService.asmx".


Regards,
Nikolay Tsenkov
the Telerik team

[Wouter]

Thanks Nikolay,

But the same error will appear again.

Greetz,
Wouter

[Helen]

Hello Wouter,

Could you please try to determine the exact error message from the server? You can do so using Fiddler or Firebug to inspect the response to the Web Service requests.

Thank you.

Regards,
Helen
the Telerik team

[Wouter]

Hi Helen,

With fireBug I will get the following error: 500 Internal Server Error

Server Error in '/' Application.

---

Unknown web method LoadNodes.
Parameter name: methodName

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: Unknown web method LoadNodes.
Parameter name: methodName

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[ArgumentException: Unknown web method LoadNodes. Parameter name: methodName] System.Web.Script.Services.WebServiceData.GetMethodData(String methodName) +526258 System.Web.Script.Services.RestHandler.CreateHandler(WebServiceData webServiceData, String methodName) +10 System.Web.Script.Services.RestHandler.CreateHandler(HttpContext context) +152 System.Web.Script.Services.RestHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated) +62 System.Web.Script.Services.ScriptHandlerFactory.GetHandler(HttpContext context, String requestType, String url, String pathTranslated) +47 System.Web.HttpApplication.MapHttpHandler(HttpContext context, String requestType, VirtualPath path, String pathTranslated, Boolean useAppConfig) +203 System.Web.MapHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +128 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +184

 

---

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.1

 

I will hope you can solve this issue.

Regards,
Wouter

[Helen]

Hi Wouter,

Please remove the "static" declaration from the RadTreeNodeData[]  web method:

http://stackoverflow.com/questions/1263379/why-are-static-methods-not-usable-as-web-service-operations-in-asmx-web-services

Regards,
Helen
the Telerik team

[Wouter]

Thank you Helen, this issue is solved!

Regards
Wouter