Can anyone tell me the best way to handle a confirmation for a delete on Gridviews?

Thanks

One way is to handle the RowDataBound event, and add an onclick attrinbute to the delete button, which calls a confirm('are you sure you want to delete?').

Hi

You can call the javascript function on the OnClientClick event of the Control or you can directly call the confirmation script on the onClientClick event. 

First way 

<script language="javascript">

function delconfirm()
    { 
            return confirm("Are you sure you want to delete this/these record/s?");
    }

</script>

 <asp:TemplateField HeaderText="Delete">
                                                            <ItemStyle HorizontalAlign="Center" Width="5%" />
                                                            <ItemTemplate>
                                                                <asp:ImageButton ID="btndelete" runat="server" CommandName="delete_record" CommandArgument='<%# Eval("id") %>'
                                                                    Height="20px" ImageUrl="~/images/button-delete.gif" Width="55px" OnClientClick="return delconfirm();" />

                                                            </ItemTemplate>
                                                            <HeaderStyle HorizontalAlign="Center" Width="5%" />
                                                        </asp:TemplateField>

Second Way 

 <asp:LinkButton ID="lnkDelete" runat="server" OnClientClick="return confirm('Are you sure want to delete this item(s) ?')"></asp:LinkButton>