AddressFamily Enum

Definition

Specifies the addressing scheme that an instance of the Socket class can use.

public enum AddressFamily
Inheritance
AddressFamily

Fields

Name Value Description
Unknown -1

Unknown address family.

Unspecified 0

Unspecified address family.

Unix 1

Unix local to host address.

InterNetwork 2

Address for IP version 4.

3

ARPANET IMP address.

Pup 4

Address for PUP protocols.

Chaos 5

Address for MIT CHAOS protocols.

Ipx 6

IPX or SPX address.

NS 6

Address for Xerox NS protocols.

Iso 7

Address for ISO protocols.

Osi 7

Address for OSI protocols.

Ecma 8

European Computer Manufacturers Association (ECMA) address.

DataKit 9

Address for Datakit protocols.

Ccitt 10

Addresses for CCITT protocols, such as X.25.

Sna 11

IBM SNA address.

DecNet 12

DECnet address.

13

Direct data-link interface address.

Lat 14

LAT address.

HyperChannel 15

NSC Hyperchannel address.

AppleTalk 16

AppleTalk address.

NetBios 17

NetBios address.

VoiceView 18

VoiceView address.

FireFox 19

FireFox address.

Banyan 21

Banyan address.

Atm 22

Native ATM services address.

InterNetworkV6 23

Address for IP version 6.

Cluster 24

Address for Microsoft cluster products.

Ieee12844 25

IEEE 1284.4 workgroup address.

Irda 26

IrDA address.

NetworkDesigners 28

Address for Network Designers OSI gateway-enabled protocols.

Max 29

MAX address.

Packet 65536

Low-level Packet address.

ControllerAreaNetwork 65537

Controller Area Network address.

Examples

The following example creates a Socket using the InterNetwork AddressFamily.

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

public class Sample
{

  public static string DoSocketGet(string server)
  {
    //Set up variables and String to write to the server.
    Encoding ASCII = Encoding.ASCII;
    string Get = "GET / HTTP/1.1\r\nHost: " + server +
                 "\r\nConnection: Close\r\n\r\n";
    Byte[] ByteGet = ASCII.GetBytes(Get);
    Byte[] RecvBytes = new Byte[256];
    String strRetPage = null;

    // IPAddress and IPEndPoint represent the endpoint that will
    //   receive the request.
    // Get first IPAddress in list return by DNS.

    try
    {

      // Define those variables to be evaluated in the next for loop and
      // then used to connect to the server. These variables are defined
      // outside the for loop to make them accessible there after.
      Socket s = null;
      IPEndPoint hostEndPoint;
      IPAddress hostAddress = null;
      int conPort = 80;

      // Get DNS host information.
      IPHostEntry hostInfo = Dns.GetHostEntry(server);
      // Get the DNS IP addresses associated with the host.
      IPAddress[] IPaddresses = hostInfo.AddressList;

      // Evaluate the socket and receiving host IPAddress and IPEndPoint.
      for (int index=0; index<IPaddresses.Length; index++)
      {
        hostAddress = IPaddresses[index];
        hostEndPoint = new IPEndPoint(hostAddress, conPort);


        // Creates the Socket to send data over a TCP connection.
        s = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp );


        // Connect to the host using its IPEndPoint.
        s.Connect(hostEndPoint);

        if (!s.Connected)
        {
          // Connection failed, try next IPaddress.
          strRetPage = "Unable to connect to host";
          s = null;
          continue;
        }

        // Sent the GET request to the host.
        s.Send(ByteGet, ByteGet.Length, 0);

      } // End of the for loop.


      // Receive the host home page content and loop until all the data is received.
      Int32 bytes = s.Receive(RecvBytes, RecvBytes.Length, 0);
      strRetPage = "Default HTML page on " + server + ":\r\n";
      strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, bytes);

      while (bytes > 0)
      {
        bytes = s.Receive(RecvBytes, RecvBytes.Length, 0);
        strRetPage = strRetPage + ASCII.GetString(RecvBytes, 0, bytes);
      }

    } // End of the try block.

    catch(SocketException e)
    {
      Console.WriteLine("SocketException caught!!!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }
    catch(ArgumentNullException e)
    {
      Console.WriteLine("ArgumentNullException caught!!!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }
    catch(NullReferenceException e)
    {
      Console.WriteLine("NullReferenceException caught!!!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }
    catch(Exception e)
    {
      Console.WriteLine("Exception caught!!!");
      Console.WriteLine("Source : " + e.Source);
      Console.WriteLine("Message : " + e.Message);
    }

    return strRetPage;
}
   public static void Main()
   {
      Console.WriteLine(DoSocketGet("localhost"));
   }
 }

Remarks

An AddressFamily member specifies the addressing scheme that a Socket will use to resolve an address. For example, InterNetwork indicates that an IP version 4 address is expected when a Socket connects to an endpoint.

Applies to

Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

See also