异步方法

 

using  System;
using  System.Data;
using  System.Configuration;
using  System.Web;
using  System.Web.Security;
using  System.Web.UI;
using  System.Web.UI.HtmlControls;
using  System.Web.UI.WebControls;
using  System.Web.UI.WebControls.WebParts;

using  Common;

namespace  web
{
     //  异步发送邮件委托
     public   delegate   void  DelegateMail();

     ///   <summary>
     ///  异步类
     ///   </summary>
     public   class  Async
    {
         #region  异步发送邮件

         public   static   void  SendMail(CMail mail)
        {
             //  实例化委托并初赋值
            DelegateMail dm  =   new  DelegateMail(mail.Send);
             //  实例化回调方法
             //  把AsyncCallback看成Delegate你就懂了，实际上AsyncCallback是一种特殊的Delegate，就像Event似的
            AsyncCallback acb  =   new  AsyncCallback(MailCallBack);
            dm.BeginInvoke(acb, dm);
        }

         public   static   void  MailCallBack(IAsyncResult result)
        {
             //  从异步状态ar.AsyncState中，获取委托对象
            DelegateMail dm  =  (DelegateMail)result.AsyncState;
             //  一定要EndInvoke
            dm.EndInvoke(result);
        }

         #endregion
    }

    

}