Socket編程--簡單非同步(異步)服務端與客戶端示例

叁歲伎倆 2022-08-25 08:54 143阅读 0赞

以下非同步(異步)示例全部使用tcp協議.

1.在編寫服務端及客戶端代碼之前,先編寫一個共用的用於保存接收信息的類:

// 接收到的數據 State object for receiving data from remote device.    
  public  class  StateObject  
\{  
 //  Client socket.    
  public  Socket workSocket  =  null ;  
 //  Size of receive buffer.    
  public  const  int  BufferSize  =  256 ;  
 //  Receive buffer.    
  public  byte \[\] buffer  =  new  byte \[BufferSize\];  
 //  Received data string.    
  public  StringBuilder sb  =  new  StringBuilder();  
\}

2.服務端示例:

示例程序创建一个接收来自客户端的连接请求的服务器。该服务器是用异步套接字生成的，因此在等待来自客户端的连接时不挂起服务器应用程序的执行。该应用程序接收来自客户端的字符串，在控制台显示该字符串，然后将该字符串回显到客户端。来自客户端的字符串必须包含字符串“<EOF>”， 以发出表示消息结尾的信号。

public  class  AsynchronousSocketListener  
\{  
 //  定義線程標識    
  public  static  ManualResetEvent allDone  =  new  ManualResetEvent( false );  
 public  AsynchronousSocketListener()  
\{  
\}  
 public  static  void  StartListening()  
\{  
 //  暫存接收數據   
  byte \[\] bytes  =  new  Byte\[ 1024 \];  
 //  建立本地端口  
 //  The DNS name of the computer running the listener is "host.contoso.com".    
  IPHostEntry ipHostInfo  =  Dns.GetHostEntry(Dns.GetHostName());  
IPAddress ipAddress  =  ipHostInfo.AddressList\[ 0 \];  
IPEndPoint localEndPoint  =  new  IPEndPoint(ipAddress,  11000 );  
 //  建立socket   
  Socket listener  =  new  Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);  
 //  Bind本地端口並偵聽連接   
  try   
\{  
listener.Bind(localEndPoint);  
listener.Listen( 100 );  
 while  ( true )  
\{  
 //  Set the event to nonsignaled state.    
  allDone.Reset();  
 //  開始偵聽    
  Console.WriteLine( " Waiting for a connection... " );  
listener.BeginAccept( new  AsyncCallback(AcceptCallback), listener);  
 //  暫停直到有新的連接 Wait until a connection is made before continuing.    
  allDone.WaitOne();  
\}  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
Console.WriteLine( "  Press ENTER to continue... " );  
Console.Read();  
\}  
 public  static  void  AcceptCallback(IAsyncResult ar)  
\{  
 //  標識主線程繼續    
  allDone.Set();  
 //  Get the socket that handles the client request.    
  Socket listener  =  (Socket)ar.AsyncState;  
Socket handler  =  listener.EndAccept(ar);  
 //  Create the state object.    
  StateObject state  =  new  StateObject();  
state.workSocket  =  handler;  
handler.BeginReceive(state.buffer,  0 , StateObject.BufferSize,  0 ,  new  AsyncCallback(ReadCallback), state);  
\}  
 public  static  void  ReadCallback(IAsyncResult ar)  
\{  
String content  =  String.Empty;  
 //  Retrieve the state object and the handler socket  
 //  from the asynchronous state object.    
  StateObject state  =  (StateObject)ar.AsyncState;  
Socket handler  =  state.workSocket;  
 //  Read data from the client socket.    
  int  bytesRead  =  handler.EndReceive(ar);  
 if  (bytesRead  >  0 )  
\{  
 //  There might be more data, so store the data received so far.    
  state.sb.Append(Encoding.ASCII.GetString(state.buffer,  0 , bytesRead));  
 //  檢查是否含有文件尾標識,如果沒有,繼續讀取數據   
  content  =  state.sb.ToString();  
 if  (content.IndexOf( " <EOF> " )  >  \- 1 )  
\{  
 //  顯示接收到的數據    
  Console.WriteLine( " Read \{0\} bytes from socket. Data : \{1\} " , content.Length, content);  
 //  發送數據 Echo the data back to the client.    
  Send(handler, content);  
\}  
 else   
\{  
 //  繼續接收數據    
  handler.BeginReceive(state.buffer,  0 , StateObject.BufferSize,  0 ,  new  AsyncCallback(ReadCallback), state);  
\}  
\}  
\}  
 private  static  void  Send(Socket handler, String data)  
\{  
 //  將字符串轉化為字節數組   
  byte \[\] byteData  =  Encoding.ASCII.GetBytes(data);  
 //  開始發送數據    
  handler.BeginSend(byteData,  0 , byteData.Length,  0 ,  new  AsyncCallback(SendCallback), handler);  
\}  
 private  static  void  SendCallback(IAsyncResult ar)  
\{  
 try   
\{  
 //  Retrieve the socket from the state object.    
  Socket handler  =  (Socket)ar.AsyncState;  
 //  完成發送數據   
  int  bytesSent  =  handler.EndSend(ar);  
Console.WriteLine( " Sent \{0\} bytes to client. " , bytesSent);  
handler.Shutdown(SocketShutdown.Both);  
handler.Close();  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 public  static  int  Main(String\[\] args)  
\{  
StartListening();  
 return  0 ;  
\}  
  
\}

3.客戶端示例:

示例程序创建一个连接到服务器的客户端。该客户端是用异步套接字生成的，因此在等待服务器返回响应时不挂起客户端应用程序的执行。该应用程序将字符串发送到服务器，然后在控制台显示该服务器返回的字符串。

public  class  AsynchronousClient  
\{  
 //  定義遠程端口   
  private  const  int  port  =  11000 ;  
 //  ManualResetEvent instances signal completion.    
  private  static  ManualResetEvent connectDone  =  new  ManualResetEvent( false );  
 private  static  ManualResetEvent sendDone  =  new  ManualResetEvent( false );  
 private  static  ManualResetEvent receiveDone  =  new  ManualResetEvent( false );  
 //  接收到的數據 The response from the remote device.    
  private  static  String response  =  String.Empty;  
 private  static  void  StartClient()  
\{  
 //  連接遠程設備   
  try   
\{  
 //  建立遠程端口    
  IPHostEntry ipHostInfo  =  Dns.GetHostEntry( " host.contoso.com " );  
IPAddress ipAddress  =  ipHostInfo.AddressList\[ 0 \];  
IPEndPoint remoteEP  =  new  IPEndPoint(ipAddress, port);  
 //  建立socket   
  Socket client  =  new  Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);  
 //  連接遠程端口   
  client.BeginConnect(remoteEP,  new  AsyncCallback(ConnectCallback), client);  
connectDone.WaitOne();  
 //  發送數據   
  Send(client,  " This is a test<EOF> " );  
sendDone.WaitOne();  
 //  接收數據   
  Receive(client);  
receiveDone.WaitOne();  
 //  顯示接收到的數據   
  Console.WriteLine( " Response received : \{0\} " , response);  
 //  關閉socket    
  client.Shutdown(SocketShutdown.Both);  
client.Close();  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 private  static  void  ConnectCallback(IAsyncResult ar)  
\{  
 try   
\{  
 //  Retrieve the socket from the state object.    
  Socket client  =  (Socket)ar.AsyncState;  
 //  完成連接   
  client.EndConnect(ar);  
Console.WriteLine( " Socket connected to \{0\} " ,  
client.RemoteEndPoint.ToString());  
 //  標識連接完成   
  connectDone.Set();  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 private  static  void  Receive(Socket client)  
\{  
 try   
\{  
 //  Create the state object.    
  StateObject state  =  new  StateObject();  
state.workSocket  =  client;  
 //  開始接收數據    
  client.BeginReceive(state.buffer,  0 , StateObject.BufferSize,  0 ,  new  AsyncCallback(ReceiveCallback), state);  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 private  static  void  ReceiveCallback(IAsyncResult ar)  
\{  
 try   
\{  
 //  Retrieve the state object and the client socket  
 //  from the asynchronous state object.    
  StateObject state  =  (StateObject)ar.AsyncState;  
Socket client  =  state.workSocket;  
 //  Read data from the remote device.    
  int  bytesRead  =  client.EndReceive(ar);  
 if  (bytesRead  >  0 )  
\{  
 //  There might be more data, so store the data received so far.    
  state.sb.Append(Encoding.ASCII.GetString(state.buffer,  0 , bytesRead));  
 //  繼續接收數據    
  client.BeginReceive(state.buffer,  0 , StateObject.BufferSize,  0 ,  new  AsyncCallback(ReceiveCallback), state);  
\}  
 else   
\{  
 // 數據接收完後,顯示數據.   
  if  (state.sb.Length  >  1 )  
\{  
response  =  state.sb.ToString();  
\}  
 // 標識數據接收完畢   
  receiveDone.Set();  
\}  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 private  static  void  Send(Socket client, String data)  
\{  
 // 將字符串轉化為ascii字節數組   
  byte \[\] byteData  =  Encoding.ASCII.GetBytes(data);  
 //  開始發送數據    
  client.BeginSend(byteData,  0 , byteData.Length,  0 ,  new  AsyncCallback(SendCallback), client);  
\}  
 private  static  void  SendCallback(IAsyncResult ar)  
\{  
 try   
\{  
 //  Retrieve the socket from the state object.    
  Socket client  =  (Socket)ar.AsyncState;  
 //  完成發送數據   
  int  bytesSent  =  client.EndSend(ar);  
Console.WriteLine( " Sent \{0\} bytes to server. " , bytesSent);  
 //  標識數據發送完畢    
  sendDone.Set();  
\}  
 catch  (Exception e)  
\{  
Console.WriteLine(e.ToString());  
\}  
\}  
 public  static  int  Main(String\[\] args)  
\{  
StartClient();  
 return  0 ;  
\}  
  
\}

參考文獻: 1. [http://www.jb51.net/html/200703/85/8049.htm][http_www.jb51.net_html_200703_85_8049.htm]

[http_www.jb51.net_html_200703_85_8049.htm]: http://www.jb51.net/html/200703/85/8049.htm