Asp.net定时控件

    using System;
    using System.Web.UI;
    using System.Web.UI.WebControls;
    using System.ComponentModel;

    [assembly:TagPrefix("Beyondbit.App.Web.UI.WebControls", "BBit")]
    namespace Beyondbit.App.Web.UI.WebControls
    {

     #region ElapsedEventArgs  class
     public class ElapsedEventArgs  : EventArgs
     {
      public int SignalTime;
     }
     #endregion

     /// <summary>
     /// 客户端定时器
     /// </summary>
     [DefaultProperty("Enabled"),
      ToolboxData("<{0}:ClientTimer runat=server></{0}:ClientTimer>")]
     public class ClientTimer : System.Web.UI.Control , System.Web.UI.IPostBackEventHandler // , System.Web.UI.IPostBackDataHandler
     {
      public delegate void ElapsedEventHandler( object sender, ElapsedEventArgs e );
      public event ElapsedEventHandler Elapsed;

      protected virtual void OnElapsed( ElapsedEventArgs e)
      {
       if ( Elapsed != null )
        Elapsed(this, e);
      }

      private int signalTime = 0;

      private int interval = 0 ;
      [Description("设置或获取定时时间(毫秒)")]
      public int Interval
      {
       set
       {
        if( value <= 0 )
         throw new ArgumentException( "Interval时间间隔不能小于或等于0" );
        interval = value ;
       }
       get
       {
        return interval ;
       }
      }

      private bool enabled = false ;
      [Description("设置或获取定时器是否启用")]
      public bool Enabled
      {
       set{ enabled = value ; }
       get{ return enabled ;  }
      }

     //public bool AutoReset = false ;

      [Description("停止定时器")]
      public void Stop()
      {
       enabled = false ;
      }

      protected override void OnPreRender(EventArgs e)
      {
       base.OnPreRender (e);

       if( this.enabled == false ) return;

       if( interval == 0 ) throw new ArgumentException( "定时器已启动，但Interval时间间隔没有设置" );

       //js
       string jsId = this.UniqueID + "_js";
       string clientFunction = this.UniqueID + "_OnElapsed";

       signalTime = signalTime + this.interval ;

       string js = "<script language='javascript'>" +
        "window.setTimeout( "+clientFunction+" , "+ this.signalTime +" );" +
        "function " + clientFunction + "(){" +
         Page.GetPostBackEventReference( this , "" + this.signalTime ) +
        ";}" +
        "</script> ";

       Page.RegisterStartupScript( jsId , js );

      }

      /// <summary>
      /// 将此控件呈现给指定的输出参数。
      /// </summary>
      /// <param name="output"> 要写出到的 HTML 编写器 </param>
      protected override void Render(HtmlTextWriter output)
      {
       //output.Write(Text);
      }

      #region IPostBackEventHandler 成员

      public void RaisePostBackEvent( string eventArgument )
      {
       if( eventArgument == "" ) throw new Exception( "eventArgument参数为空！" );
       signalTime = int.Parse( eventArgument ) ;

      ElapsedEventArgs e = new ElapsedEventArgs();
       e.SignalTime = signalTime ;

       this.OnElapsed( e );
      }

      #endregion

      #region IPostBackDataHandler 成员

    //  public void RaisePostDataChangedEvent()
    //  {
    //   // TODO:  添加 ClientTimer.RaisePostDataChangedEvent 实现
    //  }
    //
    //  public bool LoadPostData(string postDataKey, System.Collections.Specialized.NameValueCollection postCollection)
    //  {
    //   // TODO:  添加 ClientTimer.LoadPostData 实现
    //
    //   string s = postCollection[ this.UniqueID + "_signalTime" ];
    //   if( s == null s == "" ) return false;
    //
    //   signalTime = Convert.ToInt32( s );
    //
    //   return false;
    //  }

      #endregion
     }
    }