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Cascading dropdown not posting back even though autopostback=true?

Posted By:      Posted Date: October 08, 2010    Points: 0   Category :ASP.Net

I have the following code:

<asp:DropDownList ID="ddlCountries" AutoPostBack="true" runat="server">
<cc1:cascadingdropdown ID="cddCountries" runat="server" Category="Country" Enabled="True" LoadingText="loading" PromptText="choose country"
    ServiceMethod="GetCountries" ServicePath="geolocation.asmx" TargetControlID="ddlCountries">

code behind
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
End Sub

Private Sub ShowSearchResults()

End Sub

Why is the ShowSearchResults method not called when I change a value in the ddlCountries dropdown, even though I have autopostback="true" on it.

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