I have come to an issue like the server tag is not well. this code is ASP.NET C# code.
<asp:TemplateColumn HeaderText="Options">
<ItemTemplate>
<asp:ImageButton ID="imgbuttEditVendor" runat="server" CommandName="Edit" CommandArgument="<%# Eval("ctpv_id") %>" ImageUrl="~/images/buttons/edit.gif" />
</ItemTemplate>
</asp:TemplateColumn>