How to "Select All" ItemTemplate CheckBoxes in a RadComboBox?

[Jason Zam]

Hello,

I have a RadComboBox and have created a Checkbox column via an ItemTemplate.  The RadComboBox is bound dynamically in the code behind. 

Is there an easy way to insert a default record for the RadComboBox on databind, then once that first default record is selected by the user, the rest of the checkboxes in the RadComboBox are selected (acting as a "select all" checkbox)?

Here's my ASPX Code:

<telerik:RadComboBox ID="ddlProjects" EnableScreenBoundaryDetection="False" EmptyMessage="Select Project(s)"  runat="server">
   <ItemTemplate>
      <asp:CheckBox runat="server" ID="CheckBox" Text="" /> <%#DataBinder.Eval(Container, "Text")%>
   </ItemTemplate>
</telerik:RadComboBox>

Here's id my VB Code:

    Protected Sub ddlProjects_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles ddlProjects.Load
        Try
            If Not Page.IsPostBack Then
                ddlProjects.DataSource = l_oUniversal.PopulateDropDownList("sprocSchedule_Get_ProjectNames")
                ddlProjects.DataValueField = "ProjectID"
                ddlProjects.DataTextField = "ProjectName"
                ddlProjects.DataBind()
                ddlProjects.Items.Insert(0, New RadComboBoxItem(""))
            End If
        Catch ex As Exception
            ' Log Error
        End Try
    End Sub

Thanks!
Jason

[Jason Zam]

I resolved this issue myself via a Javascript method which is called on the Itemtemplate CheckBox