Basic Knowledge/Tutorial Programming About Socket in .NET

The Socket class provides a rich set of methods and properties for network communications. The Socket class allows you to perform both synchronous and asynchronous data transfer using any of the communication protocols listed in the ProtocolType enumeration.

The Socket class follows the .NET Framework naming pattern for asynchronous methods. For example, the synchronous Receive method corresponds to the asynchronous BeginReceive and EndReceive methods.



If your application only requires one thread during execution, use the following methods, which are designed for synchronous operation mode.



If you are using a connection-oriented protocol such as TCP, your server can listen for connections using the Listen method. The Accept method processes any incoming connection requests and returns a Socket that you can use to communicate data with the remote host. Use this returned Socket to call the Send or Receive method. Call the Bind method prior to calling the Listen method if you want to specify the local IP address and port number. Use a port number of zero if you want the underlying service provider to assign a free port for you. If you want to connect to a listening host, call the Connect method. To communicate data, call the Send or Receive method.

If you are using a connectionless protocol such as UDP, you do not need to listen for connections at all. Call the ReceiveFrom method to accept any incoming datagrams. Use the SendTo method to send datagrams to a remote host.

To process communications using separate threads during execution, use the following methods, which are designed for asynchronous operation mode.

If you are using a connection-oriented protocol such as TCP, use the Socket, BeginConnect, and EndConnect methods to connect with a listening host. Use the BeginSend and EndSend or BeginReceive and EndReceive methods to communicate data asynchronously. Incoming connection requests can be processed using BeginAccept and EndAccept.

If you are using a connectionless protocol such as UDP, you can use BeginSendTo and EndSendTo to send datagrams, and BeginReceiveFrom and EndReceiveFrom to receive datagrams.

If you perform multiple asynchronous operations on a socket, they do not necessarily complete in the order in which they are started.

When you are finished sending and receiving data, use the Shutdown method to disable the Socket. After calling Shutdown, call the Close method to release all resources associated with the Socket.

The Socket class allows you to configure your Socket using the SetSocketOption method. Retrieve these settings using the GetSocketOption method.