在DataList中加入删除确认

aspx页面:
 <asp:DataList ID="dltMonthPlan" DataKeyField='PID' runat="server" OnDeleteCommand="dltMonthPlan_DeleteCommand" OnItemCreated="dltMonthPlan_ItemCreated">
                                                        <ItemTemplate>
                                                            <img src="../../images/arrow.bmp">
                                                            <a onclick='window.open("ReadPlan.aspx?PID=<%# DataBinder.Eval(Container, "DataItem.PID") %>","","width=520px,height=400px,top=150px,left=200px,toolbar=no,scrollbars=no,resizable=no,center=yes,statusbars=no")'
                                                                href="#">
                                                                <asp:Label ID="Label22" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Plan") %>'>
                                                                </asp:Label></a>&nbsp;&nbsp;<asp:ImageButton ID="btnDel" ToolTip="删除" CommandName="Delete" runat="server" ImageUrl="../../images/del.gif" />
                                                        </ItemTemplate>
                                                    </asp:DataList>

cs代码:  

     protected void dltMonthPlan_DeleteCommand(object source, DataListCommandEventArgs e)
        {
            int pid = Int32.Parse(dltMonthPlan.DataKeys[e.Item.ItemIndex].ToString());
            schedule del = new schedule();
            int i = del.DelPlan(pid);
            if (i == 1)
                BindWeekPlan(DateTime.Parse(Session["CDate"].ToString()).Year.ToString() + "-" + Convert.ToString(DateTime.Parse(Session["CDate"].ToString()).DayOfYear / 7 + 1));
            else
                schedule.MessageBox(this, "删除失败");
        }
        public void dltMonthPlan_ItemCreated(object sender, System.Web.UI.WebControls.DataListItemEventArgs e)
        {
            if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.EditItem)
            {
                ImageButton myDeleteButton = new ImageButton();
                myDeleteButton = (ImageButton)e.Item.FindControl("btnDel");
                myDeleteButton.Attributes.Add("onclick", "return confirm('您真的要删除该记录吗？');");
            }
        }