ASP.NET

private void ShowAjaxModalDynamic(List<string> lstItems, String Message)
       {

         CheckBoxList lstchecks = new CheckBoxList();

                   for (int i = 0; i < lstItems.Count; i++)
         {
                       lstchecks.Items.Add("Unit" + lstItems[i]);
         }

         AjaxControlToolkit.ModalPopupExtender modalPop = new AjaxControlToolkit.ModalPopupExtender();
         modalPop.ID = "popUp";
         modalPop.PopupControlID = "ModalPanel"; //The Panel must exist on the markup
                   modalPop.TargetControlID = "btnComplete"; //the Button must exist on the markup
         modalPop.DropShadow = true;
                   modalPop.CancelControlID = "btnCancel"; //The Button must exist on the markup
         modalPop.BackgroundCssClass = "modalBackground";
         this.Panel1.Controls.Add(modalPop);
         this.ModalPanel.Controls.Add(lstchecks);
                   lblPanelMessage.Text = Message;
                   modalPop.Show();

       }