Dns.GetHostEntry Method (String)

Note: This method is new in the .NET Framework version 2.0.

Resolves a host name or IP address to an IPHostEntry instance.

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

public static IPHostEntry GetHostEntry (
	string hostNameOrAddress
public static IPHostEntry GetHostEntry (
	String hostNameOrAddress
public static function GetHostEntry (
	hostNameOrAddress : String
) : IPHostEntry



The host name or IP address to resolve.

Return Value

An IPHostEntry instance that contains address information about the host specified in hostNameOrAddress.

Exception typeCondition


hostNameOrAddress is a null reference (Nothing in Visual Basic).


The length of hostNameOrAddress is greater than 126 characters.


An error is encountered when resolving hostNameOrAddress.


hostNameOrAddress is an invalid IP address.

The GetHostEntry method queries a DNS server for the IP address that is associated with a host name or IP address.

When an empty string is passed as the host name, this method returns the IPv4 addresses of the local host.


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

The following example uses the GetHostEntry method to resolve an IP address to an IPHostEntry instance.

public static void DoGetHostEntry(string hostname)
    IPHostEntry host;

    host = Dns.GetHostEntry(hostname);

    Console.WriteLine("GetHostEntry({0}) returns:", hostname);

    foreach (IPAddress ip in host.AddressList)
        Console.WriteLine("    {0}", ip);

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0

.NET Compact Framework

Supported in: 2.0