Hi,
Better You would have the control in Edit template, that would be visible automatically in edit status .
<asp:TemplateField HeaderText="Name" SortExpression="FirstName">
<EditItemTemplate>
<asp:TextBox ID="TextBox1" runat="server"
Text='<%# Bind("FirstName") %>'></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="Label1" runat="server"
Text='<%# Bind("FirstName") %>'></asp:Label>
<asp:Label ID="Label2" runat="server"
Text='<%# Eval("LastName") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>