基於ASP.NET AJAX的WebPart開發與部署

編寫使用該擴充功能的WebPart最簡單的方法就是直接繼承別人寫好的AjaxBaseWebPart。下面是我用的一個。您也可以用其他的，或自己寫一個。
下面是命名空間引用部分：
using System;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Serialization;
using System.Web.UI;
using Microsoft.SharePoint.WebPartPages;
using Microsoft.SharePoint.Utilities;
using System.Web.UI.WebControls;
using System.Drawing;
以下是AjaxBaseWebPart類別的實作部分：
///

#region Constructor
public AjaxBaseWebpart()
{

}
#endregion

#region Methods
///

//create a custom validator to register the current error message with the ValidationSummary control
CustomValidator cv = new CustomValidator();
cv.ID = string.Concat("_Error_", uniqueCounter);
cv.ValidationGroup = _ValidationGroupId;
cv.Display = ValidatorDisplay.None;
cv.IsValid = false;
cv.ErrorMessage = message;

this.Controls.Add(cv);
}
else
{
//if RegisterError is called before the CreateChildControls 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.");
}
}
///

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
///

//get the existing ScriptManager if it exists on the page
_AjaxManager = ScriptManager.GetCurrent(this.Page);

if (_AjaxManager == null)
{
//create new ScriptManager and EnablePartialRendering
_AjaxManager = new ScriptManager();
_AjaxManager.EnablePartialRendering = true;

// Fix problem with postbacks and form actions (DevDiv 55525)
Page.ClientScript.RegisterStartupScript(typeof(AjaxBaseWebpart), this.ID, "_spOriginalFormAction = document.forms[0].action;", true);

//tag:"form" att:"onsubmit" val:"return _spFormOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapperOnSubmitWrapper )" blocks async postbacks after the first one
//not calling "_spFormOnSubmitWrapper()" breaks all postbacks
//returning true all the time, somewhat defeats the purpose of the _spFormOnSubmitWrapper() which is to block repetitive postbacks, but it allows MS AJAX Extensions to work properly
//its a hack that hopefully has minimal effect
if (this.Page.Form != null)
{
string formOnSubmitAtt = this.Page.Form.Attributes["onsubmit"];
if (!string.IsNullOrEmpty(formOnSubmitAtt) && formOnSubmitAtt == "return _spFormOnSubmitWrapper();")
{
this.Page.Form.Attributes["onsubmit"] = "_spFormOnSubmitWrapper();";
}

//add the ScriptManager as the first control in the Page.Form
//I don't think this actually matters, but I did it to be consistent with how you are supposed to place the ScriptManager when used declaritevly
this.Page.Form.Controls.AddAt(0, _AjaxManager);
}
}
}
#endregion

#region Properties
///