基于ASP.NET AJAX的WebPart开发与部署

ntrols override in AjaxBasePart then transfer the user to an error page using the SPUtility
                SPUtility.TransferToErrorPage("The CreateChildControls function of the AjaxBasePart has not been called.  You probably need to add \"base.CreateChildControls()\" to the top of your CreateChildControls override.");
            }
        }
        /// <summary>
        /// Needs to be called to ensure that the ValidationSummary control is registered on the page.  Any child web parts will need to have base.CreateChildControls() at the top of their own CreateChildControls override.
        /// </summary>
        protected override void CreateChildControls()
        {
            base.CreateChildControls();

            if (!this.Controls.Contains(_ErrorContainer))
            {
                _ValidationGroupId = Guid.NewGuid().ToString();

                _ErrorContainer = new ValidationSummary();
                _ErrorContainer.ID = "_ErrorContainer";
                _ErrorContainer.ValidationGroup = _ValidationGroupId;
                _ErrorContainer.BorderStyle = BorderStyle.Solid;
                _ErrorContainer.BorderWidth = Unit.Pixel(3);
                _ErrorContainer.BorderColor = Color.Red;

                this.Controls.Add(_ErrorContainer);
            }
        }
        #endregion

        #region Events
        /// <summary>
        /// Oninit fires before page load. Modifications to the page that are necessary to support Ajax are done here.
        /// </summary>
        protected override void OnInit(EventArgs e)
     &nb