Dns.GetHostAddresses Method

Returns the Internet Protocol (IP) addresses for the specified host.

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

Public Shared Function GetHostAddresses ( _
	hostNameOrAddress As String _
) As IPAddress()
Dim hostNameOrAddress As String
Dim returnValue As IPAddress()

returnValue = Dns.GetHostAddresses(hostNameOrAddress)
public static IPAddress[] GetHostAddresses (
	String hostNameOrAddress
public static function GetHostAddresses (
	hostNameOrAddress : String
) : IPAddress[]
Not applicable.



The host name or IP address to resolve.

Return Value

An array of type IPAddress that holds the IP addresses for the host that is specified by the hostNameOrAddress parameter.

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 GetHostAddresses method queries a DNS server for the IP addresses associated with a host name. If hostNameOrAddress is an IP address, this address is returned without querying the DNS server.

When an empty string is passed as the host name, this method returns the IPv4 addresses of the local host for all operating systems except Windows Server 2003; for Windows Server 2003, both IPv4 and IPv6 addresses for the local host are returned.


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

The following code example uses the GetHostAddresses method to resolve an IP address to an array of type IPAddress.

public static void DoGetHostAddresses(string hostname)
    IPAddress[] ips;

    ips = Dns.GetHostAddresses(hostname);

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

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

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0

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