System.Net.Sockets.Socket | .NET API Documentation

Socket Class

Provides the managed implementation of the socket API. The Socket class allows you to perform network operations. It supports both connection-oriented and connectionless communication protocols.

Fields

Name	Description
`Socket.SocketError`	Represents a socket error that occurred.

Constructors

Signature	Description
`public Socket(AddressFamily addressFamily, SocketType socketType, ProtocolType protocolType)`	Initializes a new instance of the `Socket` class using the specified address family, socket type, and protocol.
`public Socket(SocketInformation socketInformation)`	Initializes a new instance of the `Socket` class from the specified `SocketInformation` object.

Properties

Name	Description
`Available`	Gets the number of bytes available to be read from the socket.
`Blocking`	Gets or sets a value indicating whether the `Socket` is in blocking or non-blocking mode.
`Connected`	Gets a value indicating whether the `Socket` is connected to a remote host.
`DontFragment`	Gets or sets a value indicating whether the `Socket` can send data packets that set the Don't Fragment flag.
`DontLinger`	Gets or sets a value indicating whether a `Socket` will linger after closing.
`DualMode`	Gets or sets a value indicating whether the `Socket` supports both IPv4 and IPv6.
`EnableBroadcast`	Gets or sets a value indicating whether broadcast messages are sent and received by the `Socket`.
`Handle`	Gets the native socket handle.
`IsBound`	Gets a value indicating whether the `Socket` is bound to a local endpoint.
`LingerState`	Gets or sets a `LingerOption` object that controls lingering after a `Socket` closes.
`MulticastLoopback`	Gets or sets a value indicating whether multicast packets are sent back to the local computer when the application is listening on the same multicast group.
`NoDelay`	Gets or sets a value indicating whether the Nagle algorithm is disabled for this `Socket`.
`ProtocolType`	Gets the protocol type of the `Socket`.
`ProtocolOptions`	Gets or sets the `ProtocolOptions` for the `Socket`.
`ReceiveBufferSize`	Gets or sets the size of the buffer for incoming data.
`ReceiveTimeout`	Gets or sets the time-out value in milliseconds for blocking `Socket` receive operations.
`SendBufferSize`	Gets or sets the size of the buffer for outgoing data.
`SendTimeout`	Gets or sets the time-out value in milliseconds for blocking `Socket` send operations.
`Ttl`	Gets or sets the time-to-live value for the `Socket`.

Methods

Signature	Description
`Accept()`	Accepts a pending connection request.
`Bind(EndPoint localEP)`	Binds a `Socket` to a local endpoint.
`Close()`	Releases all resources used by the `Socket`.
`Connect(EndPoint remoteEP)`	Connects the `Socket` to a remote endpoint.
`Disconnect(bool reuseSocket)`	Disconnects the `Socket` from the current connection.
`EndAccept(IAsyncResult asyncResult)`	Completes an asynchronous accept operation.
`EndConnect(IAsyncResult asyncResult)`	Completes an asynchronous connect operation.
`EndReceive(IAsyncResult asyncResult)`	Completes an asynchronous receive operation.
`EndReceiveFrom(IAsyncResult asyncResult, ref EndPoint remoteEP)`	Completes an asynchronous receive from operation.
`EndSend(IAsyncResult asyncResult)`	Completes an asynchronous send operation.
`EndSendTo(IAsyncResult asyncResult)`	Completes an asynchronous send to operation.
`GetSocketOption(SocketOptionLevel optionLevel, SocketOptionName optionName)`	Gets a socket option.
`IOControlControl(int ioControlCode, byte[] optionInValue, byte[] optionOutValue)`	Sends a control message to the underlying system, which returns any data or status information that the system provides.
`Listen(int backlog)`	Puts a `Socket` into listening mode.
`Receive(byte[] buffer)`	Receives data from the `Socket` into a buffer.
`ReceiveFrom(byte[] buffer, ref EndPoint remoteEP)`	Receives data from a `Socket` into a buffer and retrieves the endpoint that sent the data.
`Send(byte[] buffer)`	Sends the entire buffer containing data to the remote device.
`SendTo(byte[] buffer, EndPoint remoteEP)`	Sends data to a specific endpoint.
`SetSocketOption(SocketOptionLevel optionLevel, SocketOptionName optionName, int optionValue)`	Sets a socket option.
`Shutdown(SocketShutdown how)`	Disables sends and/or receives on the `Socket`.

Example Usage

The following example demonstrates how to create a simple TCP client socket, connect to a server, send a message, and receive a response.


using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class SimpleTcpClient
{
    public static void Main(string[] args)
    {
        // Define server endpoint
        IPAddress ipAddress = IPAddress.Parse("127.0.0.1");
        int port = 13000;
        IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);

        // Create a TCP/IP socket.
        using (Socket sender = new Socket(
            ipAddress.AddressFamily,
            SocketType.Stream,
            ProtocolType.Tcp))
        {
            try
            {
                // Connect to the remote endpoint.
                sender.Connect(remoteEP);

                // Data buffer for incoming data.
                byte[] bytes = new byte[1024];

                // Send message to the server.
                string messageToSend = "Hello, Server!";
                byte[] msg = Encoding.ASCII.GetBytes(messageToSend + "\0");

                // Send the data through the socket.
                int bytesSent = sender.Send(msg);

                // Receive the response from the server.
                int bytesRec = sender.Receive(bytes);
                string response = Encoding.ASCII.GetString(bytes, 0, bytesRec);

                Console.WriteLine("Echoed test sent by client: {0}", response);

                // Release the socket.
                sender.Shutdown(SocketShutdown.Both);
            }
            catch (ArgumentNullException aea)
            {
                Console.WriteLine("ArgumentNullException : {0}", aea.ToString());
            }
            catch (SocketException se)
            {
                Console.WriteLine("SocketException : {0}", se.ToString());
            }
            catch (Exception e)
            {
                Console.WriteLine("Unexpected exception : {0}", e.ToString());
            }
        }

        Console.WriteLine("Press Enter to exit...");
        Console.ReadLine();
    }
}