/// <summary>
/// Callback function to accpect an incoming connection
/// </summary>
/// <param name="ar"></param>
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;
ConnectionSocket = listener.EndAccept(ar);
// Create the state object.
TcpStateObject state = new TcpStateObject();
state.workSocket = ConnectionSocket;
ConnectionSocket.BeginReceive(state.buffer, 0, TcpStateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
/// <summary>
/// Called when a new server is connected to this client
/// </summary>
/// <param name="ar"></param>
void ConnectCallback(IAsyncResult ar)
{
try
{
// Retrieve the socket from the state object.
Socket client = (Socket)ar.AsyncState;
// Complete the connection.
client.EndConnect(ar);
// Create the state object.
TcpStateObject state = new TcpStateObject();
state.workSocket = client;
// Begin receiving the data from the remote device.
client.BeginReceive(state.buffer, 0, TcpStateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
/// <summary>
/// Read a Callback send from client
/// </summary>
/// <param name="ar"></param>
void ReadCallback(IAsyncResult ar)
{
// Retrieve the state object and the handler socket
// from the asynchronous state object.
TcpStateObject state = (TcpStateObject)ar.AsyncState;
Socket handler = state.workSocket;
// Read data from the client socket.
int bytesRead = handler.EndReceive(ar);
Console.WriteLine("Callback read on server: " + bytesRead);
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));
//flag and trigger the package event
// All the data has been read from the client.
//trigger new message event
if (PackageReceived != null)
{
PackageReceived(Encoding.ASCII.GetBytes(state.sb.ToString()));
}
//keep read is allowed so
if (!TerminateFlag)
{
//establish new message and read more
TcpStateObject newState = new TcpStateObject();
newState.workSocket = handler;
try
{
handler.BeginReceive(newState.buffer, 0, TcpStateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), newState);
}
catch (SocketException)
{ }
}
}
}
/// <summary>
/// Async send a callback to client
/// </summary>
/// <param name="ar"></param>
private 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);
//keep read is allowed so
if (!TerminateFlag)
{
//establish new message and read more
TcpStateObject newState = new TcpStateObject();
newState.workSocket = handler;
handler.BeginReceive(newState.buffer, 0, TcpStateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), newState);
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
/// <summary>
/// Read a Callback send from client
/// </summary>
/// <param name="ar"></param>
void ReadCallback(IAsyncResult ar)
{
try
{
String content = String.Empty;
// Retrieve the state object and the client socket
// from the asynchronous state object.
TcpStateObject state = (TcpStateObject)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));
// Check for end-of-file tag. If it is not there, read
// more data.
content = state.sb.ToString();
// All the data has been read from the client.
//trigger new message event
if (PackageReceived != null)
{
PackageReceived(Encoding.ASCII.GetBytes(content));
}
//establish new message and read more
TcpStateObject newState = new TcpStateObject();
newState.workSocket = client;
client.BeginReceive(state.buffer, 0, TcpStateObject.BufferSize, 0,
new AsyncCallback(ReadCallback), state);
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}