confirmation for delete button in gridview control using c#

 <asp:TemplateField ShowHeader="False">
     <ItemTemplate>
       <asp:LinkButton ID="LinkButton1" runat="server" CausesValidation="False" CommandName="Delete"
                    OnClientClick='return confirm("Are you sure you want to delete this entry?");'
                    Text="Delete" />
     </ItemTemplate>
   </asp:TemplateField>