Hi All,

Im populating a DropDownList based on selection of another DropDowList.

Here is my code :

<script language="javascript" type="text/javascript">
$(document).ready(function() {
        InitJQuery();    
    });
    
    // this function will be called after the UpdatePanel finishes processing and set up jQuery again
    function pageLoad() {
        InitJQuery();
    }
    function InitJQuery() 
    {
      
        $(".ParentList").bind("change", function() 
        { 
            var selectedValue = $(this).val();           
            var ElementId = this.id; 
            var first = ElementId.lastIndexOf('_');                                
            var second = ElementId.substring(first,0);           
            var last = ElementId.substring(ElementId.length,first);
            var PrimaryRoleId = last.replace("_","");              
            var SubCategoryId = second + "_sub_" + PrimaryRoleId;  
            var select = $("#" + SubCategoryId);
                      
            select.append("<option>please wait..</option>");
            
            $.ajax({                
                type: "POST",
                url: "http://<%=PortalAlias.HTTPAlias%>/Services/ACWebSvc.asmx/getChildData",
                data: "{'id':'" + PrimaryRoleId + "','selectedValue':'" + selectedValue + "'}",
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function(response) 
                {
                    var dataList = (typeof response.d) == 'string' ? eval('(' + response.d + ')') : response.d;
                    select.empty(); 
                      
                    if(dataList.length == 0)
                    {
                        select.append("<option class='ddheader'value='0'>-N/A-</option>");
                    }
                    else
                    { 
                                               
                        for (var i = 0; i < dataList.length; i++) 
                        {
                            select.append("<option class='ddheader'>" + dataList[i].ListName + "</option>");
                        } 
                    }                   
                },
                error: function(xhr) 
                {
                    alert(xhr.statusText);
                }
            });
        });
     }    
</script>

<tr>
<td>
<asp:DropDownList ID="acListPrimaryRole" runat="server"  CssClass="ParentList" Width="150px">
    </asp:DropDownList>
</td>
<td>
<asp:DropDownList ID="acListPrimaryCategory" runat="server" CssClass="ParentList" Width="150px">
    </asp:DropDownList>
</td>
</tr>

<tr>
<td>
<asp:DropDownList ID="sub_acListPrimaryRole" CssClass="ChildList" runat="server" Width="150px">
       <asp:ListItem Text="-Select Sub Role-" Value="0" Selected="True"></asp:ListItem>
    </asp:DropDownList>
</td>
<td>
    <asp:DropDownList ID="sub_acListPrimaryCategory" CssClass="ChildList" runat="server" Width="150px">
       <asp:ListItem Text="-Select Sub Category-" Value="0" Selected="True"></asp:ListItem>
    </asp:DropDownList>
</td>
</tr>


My WebService:

<System.Web.Script.Services.ScriptService()> _
<WebService(Namespace:="http://tempuri.org/")> _
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Public Class ACWebSvc
    'Inherits System.Web.Services.WebService
    Inherits Entities.Modules.PortalModuleBase
    Dim _prfController As ProfileController

<WebMethod()> _
    Public Function getChildData(ByVal id As String, ByVal selectedValue As String) As List(Of dataList)
        Dim _prfController As ProfileController = New ProfileController
        Dim dsChild As DataSet = _prfController.Profile_GetSecondaryList(selectedValue, id)
        Dim l As New Generic.List(Of dataList)
        Dim e As New dataList("0", "Select")
        For Each row As DataRow In dsChild.Tables(0).Rows
            e = New dataList(row("ListId"), row("ListName"))
            l.Add(e)
        Next
        Return l
    End Function

Im Binding data to first dropdown list statically.

Its working fine , im able to bind the data to second dropdownlist on selection of firstdropdown list ,

This is for some search functionality ,on click if button on this page im populating some results ,But problem is im losing the selection(second list) after postback .

How to get that selection on post back ?

Hi,

When you change the selection of DropDownList, please save the selectedIndex into a hiddencontrol so that it can get the selectedIndex on serverside in button click.