[instant message]用asp.net+ jquery实现comet即时消息机制 ----转载woody.wu

效果图:

 

主要是通过后台线程来管理客户端的连接状态以及消息状态.

 webconfig配置

 

 

<appSettings>
    
<add key="IntervalTime" value="10000"/>间隔时间
    
<add key="HasDB" value="N"></add>是否查询数据库系统信息
    
<add key="ConnectInterval" value="4000"></add>连接间隔时间

  
</appSettings>

 

 

 


<httpHandlers>

      
<add verb="POST" path="ChatChannelHandler.ashx" type="MDS.Comet.ChatChannelHandler,Comet"/>发送消息
      
<add verb="*" path="ChatHandler.ashx" type="MDS.Comet.ChatHandler,Comet" validate="false"/>AJAX轮询
    
</httpHandlers>

 

1.asp.net

 当客户段第一次连接的时候通过              

ThreadPool.RegisterWaitForSingleObject(client.EventWaitHandle, new System.Threading.WaitOrTimerCallback(WaitOrTimerCallback), client, ConnectInterval, true)向线程池添加一个可以定时执行函数,

设置

public AutoResetEvent EventWaitHandle = new AutoResetEvent(false);

client.EventWaitHandle

的状态,实现立即向客户端发送消息,通过这个函数实现客户端的长连接.保持客户端的可持续性.

 

 

 

2.通过AJAX轮询

 

 



  
function SetParameters(p,pSplit)
   { 
     
var option={length:'200',title:'',help:'None'};
     properties
=p.split(pSplit);
     
for(i=0;i<properties.length;i++)
     {
            namevalue 
= properties[i].split(':');
            
if(namevalue.length >1)
            {
                execute 
="option." + namevalue[0+'=\''+ namevalue[1]+'\';';
                eval(execute);
            }
     }
     
return option;
   }


function CometClient(handler, publicToken, privateToken, onmessage, ontimeout, oncancelled, onerror)
{
    
this.lastMessageId = 1000;
    
this.publicToken = publicToken;
    
this.privateToken = privateToken;
    
this.handler = handler;
    
this.onmessage = onmessage;
    
this.ontimeout = ontimeout;
    
this.oncancelled = oncancelled;
    
this.onerror = onerror;
    
this.running = true;
}

CometClient.prototype.stopWaiting 
= function()
{
    
this.running = false;
}

CometClient.prototype.startWaiting 
= function()
{
    
this.running = true;
    
this.waitForMessages();
}

CometClient.prototype.waitForMessages 
= function()
{
    
var me = this;

    $.ajax(
    {
        url: 
this.handler,
        type: 
"POST",
        data: { privateToken: 
this.privateToken, lastMessageId: this.lastMessageId },
        success: 
function(response)
        {  
            
var messages =null;
            
if(response!=null&&response!="")
            {
 
               messages 
=SetParameters(response,";");
            }        
            
if (messages != null && messages.length > 0)
            {
                
var keepWaiting = me.running;
                
for (var i = 0; i < 1; i++)
                {
                    
if (me.lastMessageId < messages.MessageId)
                        me.lastMessageId 
= messages.MessageId;

                    
switch (messages.Name.toLowerCase())
                    {
                        
case "timedout":
                             me.ontimeout();
                            
break;
                        
case "cancelled":
                             keepWaiting 
= false;
                            me.oncancelled();
                            
break;
                        
case "message":
                            me.onmessage(messages);
                            
break;
                    }
                }
                
if (keepWaiting)
                    me.waitForMessages();
            }
        },
        error: 
function()
        {
            me.onerror();
        }
    });
}

   

 

 下载演示代码

 

 

posted @ 2010-07-21 22:55  你妹的sb  阅读(851)  评论(2编辑  收藏  举报
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