好的，首先让我说，这是我第一次尝试编写客户端/服务器软件。 我的客户端是用Java编写的Android手持设备，而Server是用C＃编写的。
我的服务器实现是从MSDN网站获取的AsyncSocketServer示例，我根据自己的需要进行了修改。
我取得的成就：
客户端可以连接到服务器。 客户端可以向服务器发送第一个请求 服务器发回请求的答案。
无效：
当客户端尝试发送另一个请求时，一切都会变坏。
下一行抛出“socketException未处理”，因为我是这个服务器端的新手，我不知道我在做什么来搞砸它。
// Read data from the client socket.
int bytesRead = handler.EndReceive(ar);
例外：
A first chance exception of type 'System.Net.Sockets.SocketException' occurred in System.dll
A first chance exception of type 'System.Net.Sockets.SocketException' occurred in System.dll
System.Net.Sockets.SocketException (0x80004005): An established connection was aborted by the software in your host machine
at System.Net.Sockets.Socket.EndReceive(IAsyncResult asyncResult)
at PlayServer.Network.AsynchronousSocketListener.ReadCallback(IAsyncResult ar) in c:\Users\Unknown\Documents\Visual Studio 2013\Projects\WpfApplication1\WpfApplication1\Network\TCPServer.cs:line 130
我的服务器代码：
namespace PlayServer.Network
{
// State object for reading client data asynchronously
public class StateObject
{
// Client socket.
public Socket workSocket = null;
// Size of receive buffer.
public const int BufferSize = 1024;
// Receive buffer.
public byte[] buffer = new byte[BufferSize];
// Received data string.
public StringBuilder sb = new StringBuilder();
}
public class AsynchronousSocketListener
{
// Thread signal.
public static ManualResetEvent allDone = new ManualResetEvent(false);
public static CountdownEvent freeToSend;
// Instances for interactions
private static PlayerUI mainW;
private static MainPlayer player = MainPlayer.Instance;
private static MessageManager messageHandler = MessageManager.Instance;
public AsynchronousSocketListener()
{
freeToSend = new CountdownEvent(1);
messageHandler.registerUI(mainW);
StartListening();
}
public static void registerUI(PlayerUI main)
{
mainW = main;
}
public static void StartListening()
{
// Data buffer for incoming data.
byte[] bytes = new Byte[1024];
// Establish the local endpoint for the socket.
// The DNS name of the computer
// running the listener is "host.contoso.com".
IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());
IPAddress ipAddress = ipHostInfo.AddressList[0];
IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 5555);
// Create a TCP/IP socket.
Socket listener = new Socket(AddressFamily.InterNetwork,
SocketType.Stream, ProtocolType.Tcp);
// Bind the socket to the local endpoint and listen for incoming connections.
try
{
listener.Bind(localEndPoint);
listener.Listen(100);
while (true)
{
// Set the event to nonsignaled state.
allDone.Reset();
// Start an asynchronous socket to listen for connections.
Console.WriteLine("Waiting for a connection...");
listener.BeginAccept(
new AsyncCallback(AcceptCallback),
listener);
// Wait until a connection is made before continuing.
allDone.WaitOne();
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
Console.WriteLine("\nPress ENTER to continue...");
Console.Read();
}
public static void AcceptCallback(IAsyncResult ar)
{
// Signal the main thread to continue.
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);
// Read string from client
string recievedMessage = Encoding.ASCII.GetString(
state.buffer, 0, bytesRead).ToString();
// Figure what kind of message(Operation) client requested
string answerFromServer = messageHandler.figureMessageType(recievedMessage);
// Wait for JSON serialization/de-serialziation to finish and then send a reply to client
freeToSend.Wait();
Send(handler, answerFromServer);
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));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToString();
if (content.IndexOf("<EOF>") > -1)
{
// All the data has been read from the
// client. Display it on the console.
Console.WriteLine("Read {0} bytes from socket. \n Data : {1}",
content.Length, content);
// Echo the data back to the client.
Send(handler, content);
}
else
{
// Not all data received. Get more.
handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
}
private static void Send(Socket handler, String data)
{
// Convert the string data to byte data using ASCII encoding.
byte[] byteData = Encoding.ASCII.GetBytes(data);
// Begin sending the data to the remote device.
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;
// Complete sending the data to the remote device.
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());
}
}
}
}