如何处理服务器或客户端socket断开.doc

编程经验谈 如何处理socket连接后服务器端或socket编程经验谈-如何处理socket连接后服务器端或客户端的断开(转)2010年12月29日星期三14：50现象：服务器端等待客户断连接，当socket连接建立后，如果客户端异常断开，服务器会抛出异常，从而导致程序运行中断目标：希望服务器一直等待连接，客户端中断后程序不退出，而客户端重新恢复后可以继续保持连接代码：public class receivepublic static byte buffer=new byte1024；public static manualresetevent socketevent=new manualresetevent(false)；public static socket slistener=new socket(addressfamily.internetwork,sockettype.stream,protocoltype.tcp)；public static socket handler=null；public static string clientbroken=an connection was forcibly closed by the remote host；public static void receive()tryconsole.writeline(main threadid：+appdomain.getcurrentthreadid()；byte bytes=new byte1024；ipaddress ipaddr=ipaddress.parse()；int port=10001；ipendpoint epserver=new ipendpoint(ipaddr,port)；/binding asocket slistener.bind(epserver)；/start listening slistener.listen(10)；while(true)if(handler=null)/first must make aconnect console.writeline(waiting for aconnection.)；/asychronous function for accepting connections slistener.beginaccept(new asynccallback(acceptcallback),slistener)；socketevent.waitone()；handler.beginreceive(buffer,0,buffer.length,0,new asynccallback(receivecallback),handler)；socketevent.waitone()；elseconsole.writeline(waiting next message.)；socketevent.reset()；handler.beginreceive(buffer,0,buffer.length,0,new asynccallback(receivecallback),handler)；socketevent.waitone()；console.readline()；catch(exception e)console.writeline(e.tostring()；console.readline()；public static void acceptcallback(iasyncresult ar)tryconsole.writeline(acceptcallback thread id：+appdomain.getcurrentthreadid()；socket listener=(socket)ar.asyncstate；/new socket handler=listener.endaccept(ar)；handler.beginreceive(buffer,0,buffer.length,0,new asynccallback(receivecallback),handler)；catch(exception e)console.writeline(e.tostring()；public static void receivecallback(iasyncresult ar)string err_message=null；tryconsole.writeline(receivecallback thread id：+appdomain.getcurrentthreadid()；string content=string.empty；handler=(socket)ar.asyncstate；int bytesread=handler.endreceive(ar)；/if there is some data.if(bytesread 0)/append it to the main string content+=encoding.ascii.getstring(buffer,0,bytesread)；/if we encounter the end of message character if(content.indexof(char)3)-1|content.indexof(char)16)-1)console.writeline(read+content.length+bytes from socket.n data：+content)；socketevent.set()；else/otherwise receive the remaining data handler.beginreceive(buffer,0,buffer.length,0,new asynccallback(receivecallback),handler)；catch(exception e)err_message=e.message；if(err_message.indexof(an existing connection was forcibly closed by the remote host)-1)console.writeline(an existing connection was forcibly closed by the remote host)；/handler.shutdown(socketshutdown.both)；/handler.close()；console.writeline(waiting for aconnection.)；/asychronous function for accepting connections slistener.beginaccept(new asynccallback(acceptcallback),slistener)；elseconsole.writeline(e.tostring()；说明：关键在于最后这段的异常处理，接收中断后，服务器端重新等待接收。现象：客户端与服务器连接，当socket连接建立后，如果服务器端异常断开，客户端会抛出异常，从而导致程序运行中断目标：希望客户端出现提示，服务器端中断后程序不退出，而服务器端重新恢复后可以继续保持连接代码：public class asynccommpublic static string theresponse=；public static byte buffer=new byte1024；public static manualresetevent socketevent=new manualresetevent(false)；public static socket sclient=new socket(addressfamily.internetwork,sockettype.stream,protocoltype.tcp)；public static ipendpoint epserver=new ipendpoint(ipaddress.parse(),10001)；public static void send(string data)byte bytedata=null；bytedata=encoding.ascii.getbytes(data)；tryif(！sclient.connected)console.writeline(system.datetime.now.tostring(yyyy-mm-dd hh：mm：ss：ffff)+connect begining.)；sclient.beginconnect(epserver,new asynccallback(connectcallback),sclient)；socketevent.waitone()；sclient.beginsend(bytedata,0,bytedata.length,0,new asynccallback(sendcallback),sclient)；socketevent.waitone()；catch(exception e)console.writeline(server side is broken.)；socketevent.reset()；return；public static void connectcallback(iasyncresult ar)trythread thr=thread.currentthread；console.writeline(connectcallback thread state：+appdomain.getcurrentthreadid()；socket sclient=(socket)ar.asyncstate；sclient.endconnect(ar)；console.writeline(socket connected to+sclient.remoteendpoint.tostring()；socketevent.set()；catch(exception ex)console.writeline(system.datetime.now.tostring(yyyy-mm-dd hh：mm：ss：ffff)+|+appdomain.getcurrentthreadid()+|3-level 3server connection