<asp:SqlDataSource ID="gridSource" runat="server" ConnectionString="<%$ ConnectionStrings:connectionString %>"
    SelectCommand=" select * from [tbl_Capability] where domain like '%@DomainID%'">
    <SelectParameters>
        <asp:ControlParameter Name="DomainID" PropertyName="SelectedValue" ControlID="ddlcu"></asp:ControlParameter>
    </SelectParameters>
</asp:SqlDataSource>