I need to validate value on edit mode in gridview in clientside itself

Question

Can anyone help on this soon

<asp:TemplateField HeaderText="Nickname" ItemStyle-CssClass="row_1" ItemStyle-Width ="150" ItemStyle-Height="37px" >
<EditItemTemplate>
<asp:TextBox ID="txtnickname" runat="server" Text='<%#Eval("name") %>' ></asp:TextBox>
</EditItemTemplate>
<ItemTemplate>
<asp:Label ID="lblitemnickname" runat="server" Text='<%#Eval("name") %>' />
</ItemTemplate>
</asp:TemplateField>

Here i need to validate the txtnickname value on edit mode in gridview in clientside itself...

Can anyone help on this soon

Thanks in advance