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Dns.GetHostByName Method

Note: This API is now obsolete.

Gets the DNS information for the specified DNS host name.

Namespace:  System.Net
Assembly:  System (in System.dll)

[ObsoleteAttribute("GetHostByName is obsoleted for this type, please use GetHostEntry instead. http://go.microsoft.com/fwlink/?linkid=14202")]
public static IPHostEntry GetHostByName(
	string hostName
)

Parameters

hostName
Type: System.String

The DNS name of the host.

Return Value

Type: System.Net.IPHostEntry
An IPHostEntry object that contains host information for the address specified in hostName.

ExceptionCondition
ArgumentNullException

hostName is null.

ArgumentOutOfRangeException

The length of hostName is greater than 255 characters.

SocketException

An error is encountered when resolving hostName.

The GetHostByName method queries the Internet DNS server for host information. If you pass an empty string as the host name, this method retrieves the standard host name for the local computer.

For asynchronous access to DNS information, use the BeginGetHostByName and EndGetHostByName methods.

If the Ipv6Element.Enabled property is set to true, the Aliases property of the IPHostEntry instance returned is not populated by this method and will always be empty.

NoteNote

This member emits trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.

The following example uses the GetHostByName method to get the DNS information for the specified DNS host name.

      try 
      {
         IPHostEntry hostInfo = Dns.GetHostByName(hostName);
         // Get the IP address list that resolves to the host names contained in the  
         // Alias property.
         IPAddress[] address = hostInfo.AddressList;
         // Get the alias names of the addresses in the IP address list.
         String[] alias = hostInfo.Aliases;

         Console.WriteLine("Host name : " + hostInfo.HostName);
         Console.WriteLine("\nAliases : ");
         for(int index=0; index < alias.Length; index++) {
           Console.WriteLine(alias[index]);
         } 
         Console.WriteLine("\nIP address list : ");
         for(int index=0; index < address.Length; index++) {
            Console.WriteLine(address[index]);
         }
      }
      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(Exception e)
	  {
		  Console.WriteLine("Exception caught!!!");
		  Console.WriteLine("Source : " + e.Source);
		  Console.WriteLine("Message : " + e.Message);
	  }

.NET Framework

Supported in: 1.1, 1.0
Obsolete (compiler warning) in 4.5.2
Obsolete (compiler warning) in 4.5.1
Obsolete (compiler warning) in 4.5
Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5
Obsolete (compiler warning) in 3.5 SP1
Obsolete (compiler warning) in 3.0
Obsolete (compiler warning) in 3.0 SP1
Obsolete (compiler warning) in 3.0 SP2
Obsolete (compiler warning) in 2.0
Obsolete (compiler warning) in 2.0 SP1
Obsolete (compiler warning) in 2.0 SP2

.NET Framework Client Profile

Obsolete (compiler warning) in 4
Obsolete (compiler warning) in 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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