Hello everyone,

I'm trying to use a CascadingDropDown in a module, but I have some problems. In a separate test project, all works fine, but when I try to use the same code in a module, the function GetDropDownContents written in the WebService never fires.

Can anyone suggest me a solution?

This is the sample code:

In Control.ascx:

<div >
        <div >CascadingDropDown Demonstration</div>
        <table>
            <tr>
                <td>Make</td>
                <td><asp:DropDownList ID="DropDownList1" runat="server" Width="170" /></td>
            </tr>
            <tr>
                <td>Model</td>
                <td><asp:DropDownList ID="DropDownList2" runat="server" Width="170" /></td>
            </tr>
            <tr>
                <td>Color</td>
                <td><asp:DropDownList ID="DropDownList3" runat="server" Width="170" AutoPostBack="true"
                    OnSelectedIndexChanged="DropDownList3_SelectedIndexChanged" /></td>
            </tr>
        </table>
        <br />
       
        <cc1:CascadingDropDown ID="CascadingDropDown1" runat="server" TargetControlID="DropDownList1"
            Category="Make"  PromptText="Please select a make"  LoadingText="[Loading makes...]"
            ServicePath="CarsService.asmx" ServiceMethod="GetDropDownContents" />
        <cc1:CascadingDropDown ID="CascadingDropDown2" runat="server" TargetControlID="DropDownList2"
            Category="Model" PromptText="Please select a model" LoadingText="[Loading models...]"
            ServiceMethod="GetDropDownContentsPageMethod" ParentControlID="DropDownList1" />
        <cc1:CascadingDropDown ID="CascadingDropDown3" runat="server" TargetControlID="DropDownList3"
            Category="Color" PromptText="Please select a color" LoadingText="[Loading colors...]"
            ServicePath="CarsService.asmx" ServiceMethod="CarsService.GetDropDownContents"
            ParentControlID="DropDownList2" />
     
        <asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional" RenderMode="inline">
            <ContentTemplate>
                <asp:Label ID="Label1" runat="server" Text="[No response provided yet]" />
            </ContentTemplate>
            <Triggers>
                <asp:AsyncPostBackTrigger ControlID="DropDownList3" EventName="SelectedIndexChanged" />
            </Triggers>
        </asp:UpdatePanel>
    </div>

In Control.ascx.vb

   <WebMethod()> _
        <System.Web.Script.Services.ScriptMethod()> _
        Public Shared Function GetDropDownContentsPageMethod(ByVal knownCategoryValues As String, ByVal category As String) As CascadingDropDownNameValue()
            Return New CarsService().GetDropDownContents(knownCategoryValues, category)
        End Function

In CarsService.asmx (the service file)

%@ WebService
    Language="VB"
    CodeBehind="~/App_Code/CarsService.vb"
    Class="CarsService" %>

in CarsService.vb (the code-behind service file)

' (c) Copyright Microsoft Corporation.
' This source is subject to the Microsoft Public License.
' See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
' All other rights reserved.


Imports System
Imports System.Collections.Specialized
Imports System.Text.RegularExpressions
Imports System.Web
Imports System.Web.Services
Imports System.Xml

''' <summary>
''' Helper web service for CascadingDropDown sample
''' </summary>
<WebService([Namespace] := "http://tempuri.org/")> _
<WebServiceBinding(ConformsTo := WsiProfiles.BasicProfile1_1)> _
<System.Web.Script.Services.ScriptService()> _
Public Class CarsService
    Inherits WebService
    ' Member variables
    Private Shared _document As XmlDocument
    Private Shared _inputValidationRegex As Regex
    Private Shared _lock As New Object()
   
    ' we make these public statics just so we can call them from externally for the
    ' page method call
    Public Shared ReadOnly Property Document() As XmlDocument
        Get
            SyncLock _lock
                If _document Is Nothing Then
                    ' Read XML data from disk
                    _document = New XmlDocument()
                    _document.Load(HttpContext.Current.Server.MapPath("~/App_Data/CarsService.xml"))
                End If
            End SyncLock
            Return _document
        End Get
    End Property
   
    Public Shared ReadOnly Property Hierarchy() As String()
        Get
            Return New String() {"make", "model"}
        End Get
    End Property
   
    Public Shared ReadOnly Property InputValidationRegex() As Regex
        Get
            SyncLock _lock
                If _inputValidationRegex Is Nothing Then
                    _inputValidationRegex = New Regex("^[0-9a-zA-Z \(\)]*$")
                End If
            End SyncLock
            Return _inputValidationRegex
        End Get
    End Property
   
    ''' <summary>
    ''' Helper web service method
    ''' </summary>
    ''' <param name="knownCategoryValues">private storage format string</param>
    ''' <param name="category">category of DropDownList to populate</param>
    ''' <returns>list of content items</returns>
    <WebMethod()> _
    Public Function GetDropDownContents(ByVal knownCategoryValues As String, ByVal category As String) As AjaxControlToolkit.CascadingDropDownNameValue()
        ' Get a dictionary of known category/value pairs
        Dim knownCategoryValuesDictionary As StringDictionary = AjaxControlToolkit.CascadingDropDown.ParseKnownCategoryValuesString(knownCategoryValues)
       
        ' Perform a simple query against the data document
        Return AjaxControlToolkit.CascadingDropDown.QuerySimpleCascadingDropDownDocument(Document, Hierarchy, knownCategoryValuesDictionary, category, InputValidationRegex)
    End Function
End Class
 

thank you!

Damn!

I simply solved adding this to load function:

Try

                If DotNetNuke.Framework.AJAX.IsInstalled Then
                    DotNetNuke.Framework.AJAX.RegisterScriptManager()
                End If
            Catch exc As Exception        'Module failed to load
                ProcessModuleLoadException(Me, exc)
            End Try