============================ MSDN中的例子 Part 2/2 =========================== private void ProcessAccept(SocketAsyncEventArgs e) { Interlocked.Increment(ref m_numConnectedSockets); Console.WriteLine("Client connection accepted. There are {0} clients connected to the server", m_numConnectedSockets); // Get the socket for the accepted client connection and put it into the //ReadEventArg object user token SocketAsyncEventArgs readEventArgs = m_readWritePool.Pop(); ((AsyncUserToken)readEventArgs.UserToken).Socket = e.AcceptSocket; // As soon as the client is connected, post a receive to the connection bool willRaiseEvent = e.AcceptSocket.ReceiveAsync(readEventArgs); if(!willRaiseEvent){ ProcessReceive(readEventArgs); } // Accept the next connection request StartAccept(e); } // This method is called whenever a receive or send operation is completed on a socket // // <param name="e">SocketAsyncEventArg associated with the completed receive operation</param> void IO_Completed(object sender, SocketAsyncEventArgs e) { // determine which type of operation just completed and call the associated handler switch (e.LastOperation) { case SocketAsyncOperation.Receive: ProcessReceive(e); break; case SocketAsyncOperation.Send: ProcessSend(e); break; default: throw new ArgumentException("The last operation completed on the socket was not a receive or send"); } } // This method is invoked when an asynchronous receive operation completes. // If the remote host closed the connection, then the socket is closed. // If data was received then the data is echoed back to the client. // private void ProcessReceive(SocketAsyncEventArgs e) { // check if the remote host closed the connection AsyncUserToken token = (AsyncUserToken)e.UserToken; if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success) { //increment the count of the total bytes receive by the server Interlocked.Add(ref m_totalBytesRead, e.BytesTransferred); Console.WriteLine("The server has read a total of {0} bytes", m_totalBytesRead); //echo the data received back to the client bool willRaiseEvent = token.Socket.SendAsync(e); if (!willRaiseEvent) { ProcessSend(e); } } else { CloseClientSocket(e); } } // This method is invoked when an asynchronous send operation completes. // The method issues another receive on the socket to read any additional // data sent from the client // // <param name="e"></param> private void ProcessSend(SocketAsyncEventArgs e) { if (e.SocketError == SocketError.Success) { // done echoing data back to the client AsyncUserToken token = (AsyncUserToken)e.UserToken; // read the next block of data send from the client bool willRaiseEvent = token.Socket.ReceiveAsync(e); if (!willRaiseEvent) { ProcessReceive(e); } } else { CloseClientSocket(e); } } private void CloseClientSocket(SocketAsyncEventArgs e) { AsyncUserToken token = e.UserToken as AsyncUserToken; // close the socket associated with the client try { token.Socket.Shutdown(SocketShutdown.Send); } // throws if client process has already closed catch (Exception) { } token.Socket.Close(); // decrement the counter keeping track of the total number of clients connected to the server Interlocked.Decrement(ref m_numConnectedSockets); m_maxNumberAcceptedClients.Release(); Console.WriteLine("A client has been disconnected from the server. There are {0} clients connected to the server", m_numConnectedSockets); // Free the SocketAsyncEventArg so they can be reused by another client m_readWritePool.Push(e); }}
private void ProcessAccept(SocketAsyncEventArgs e)
{
Interlocked.Increment(ref m_numConnectedSockets);
Console.WriteLine("Client connection accepted. There are {0} clients connected to the server",
m_numConnectedSockets); // Get the socket for the accepted client connection and put it into the
//ReadEventArg object user token
SocketAsyncEventArgs readEventArgs = m_readWritePool.Pop();
((AsyncUserToken)readEventArgs.UserToken).Socket = e.AcceptSocket; // As soon as the client is connected, post a receive to the connection
bool willRaiseEvent = e.AcceptSocket.ReceiveAsync(readEventArgs);
if(!willRaiseEvent){
ProcessReceive(readEventArgs);
} // Accept the next connection request
StartAccept(e);
} // This method is called whenever a receive or send operation is completed on a socket
//
// <param name="e">SocketAsyncEventArg associated with the completed receive operation</param>
void IO_Completed(object sender, SocketAsyncEventArgs e)
{
// determine which type of operation just completed and call the associated handler
switch (e.LastOperation)
{
case SocketAsyncOperation.Receive:
ProcessReceive(e);
break;
case SocketAsyncOperation.Send:
ProcessSend(e);
break;
default:
throw new ArgumentException("The last operation completed on the socket was not a receive or send");
} } // This method is invoked when an asynchronous receive operation completes.
// If the remote host closed the connection, then the socket is closed.
// If data was received then the data is echoed back to the client.
//
private void ProcessReceive(SocketAsyncEventArgs e)
{
// check if the remote host closed the connection
AsyncUserToken token = (AsyncUserToken)e.UserToken;
if (e.BytesTransferred > 0 && e.SocketError == SocketError.Success)
{
//increment the count of the total bytes receive by the server
Interlocked.Add(ref m_totalBytesRead, e.BytesTransferred);
Console.WriteLine("The server has read a total of {0} bytes", m_totalBytesRead); //echo the data received back to the client
bool willRaiseEvent = token.Socket.SendAsync(e);
if (!willRaiseEvent)
{
ProcessSend(e);
} }
else
{
CloseClientSocket(e);
}
} // This method is invoked when an asynchronous send operation completes.
// The method issues another receive on the socket to read any additional
// data sent from the client
//
// <param name="e"></param>
private void ProcessSend(SocketAsyncEventArgs e)
{
if (e.SocketError == SocketError.Success)
{
// done echoing data back to the client
AsyncUserToken token = (AsyncUserToken)e.UserToken;
// read the next block of data send from the client
bool willRaiseEvent = token.Socket.ReceiveAsync(e);
if (!willRaiseEvent)
{
ProcessReceive(e);
}
}
else
{
CloseClientSocket(e);
}
} private void CloseClientSocket(SocketAsyncEventArgs e)
{
AsyncUserToken token = e.UserToken as AsyncUserToken; // close the socket associated with the client
try
{
token.Socket.Shutdown(SocketShutdown.Send);
}
// throws if client process has already closed
catch (Exception) { }
token.Socket.Close(); // decrement the counter keeping track of the total number of clients connected to the server
Interlocked.Decrement(ref m_numConnectedSockets);
m_maxNumberAcceptedClients.Release();
Console.WriteLine("A client has been disconnected from the server. There are {0} clients connected to the server", m_numConnectedSockets); // Free the SocketAsyncEventArg so they can be reused by another client
m_readWritePool.Push(e);
}}
感觉就事件本身来说没有多大区别，只是处理上有所不同
第一个事件用来收发，第二个事件中间接的递归(通过调用StartAccept(e))使得可以持续的接收
连接请求
如果客户端掉线只能等待超时异常了，不过搜搜好像有方法解决的