I have 3 dropdown list 1) DrpSchool_College 2) DrpSchool_College_Type 3) DrpSchool_College_Name ASPX:- 1st dropdown list:- <asp:DropDownList ID="DrpSchoolCollege" runat="server" AutoPostBack="true" OnSelectedIndexChanged="DrpSchoolCollege_SelectedIndexChanged" > <asp:ListItem Selected="True" Text="Select School / College ..." Value="Select School / College ..."></asp:ListItem> <asp:ListItem Text="School" Value="School"></asp:ListItem> <asp:ListItem Text="College" Value="College"></asp:ListItem> </asp:DropDownList> <asp:CompareValidator ID="CompareValidator2" runat="server" ControlToValidate="DrpSchoolCollege" Font-Bold="true" Font-Size="Large" ErrorMessage="*" Operator="NotEqual" Validat ...

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