Adding Client-Side Confirmation When Deleting

http://www.asp.net/data-access/tutorials/adding-client-side-confirmation-when-deleting-cs

Here's some example code

<asp:LinkButton ID="DeleteButton" runat="server" CausesValidation="True" 
                        CommandName="Delete" Text="Delete" OnClientClick="return confirm('Are you sure you wish to delete this record?');" />