Recuperare valori da drop dinamici

Protected Sub ddl_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs)
            Dim ddlTest As DropDownList = CType(sender, DropDownList)
            Dim SelectedIndex As Integer = ddlTest.SelectedIndex
        End Sub

For i As Integer = 1 To 4
   Dim ddlTest As New DropDownList
   ddlTest.id = i.ToString()
   AddHandler ddlTest.SelectedIndexChanged, AddressOf ddl_SelectedIndexChanged
   controls.add(ddlTest)
Next

<asp:repeater id="rptTest" runat="server">
   <asp:dropdownlist SelectedIndexChange="ddl_SelectedIndexChange" DataSource="...." />
</asp:repeater>