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NetworkChange.NetworkAddressChanged Event

Occurs when the IP address of a network interface changes.

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

public static event NetworkAddressChangedEventHandler NetworkAddressChanged

The NetworkChange class raises NetworkAddressChanged events when the address of a network interface, also called a network card or adapter, changes.

To have a NetworkChange object call an event-handling method when a NetworkAddressChanged event occurs, you must associate the method with a NetworkAddressChangedEventHandler delegate, and add this delegate to this event.

The NetworkAddressChanged event is supported on Windows 2000 and later.

The following code example listens for address changes and displays the status of network interfaces when a NetworkAddressChanged event occurs.

using System;
using System.Net;
using System.Net.NetworkInformation;

namespace Examples.Net.AddressChanges
{
    public class NetworkingExample
    {
        public static void Main()
        {
            NetworkChange.NetworkAddressChanged += new 
            NetworkAddressChangedEventHandler(AddressChangedCallback);
            Console.WriteLine("Listening for address changes. Press any key to exit.");
            Console.ReadLine();
        }
        static void AddressChangedCallback(object sender, EventArgs e)
        {

            NetworkInterface[] adapters = NetworkInterface.GetAllNetworkInterfaces();
            foreach(NetworkInterface n in adapters)
            {
                Console.WriteLine("   {0} is {1}", n.Name, n.OperationalStatus);
            }
        }
    }
}
#using <mscorlib.dll>
#using <System.dll>
using namespace System;
using namespace System::Net;
using namespace System::Net::NetworkInformation;

void AddressChangedCallback(Object* /*sender*/, EventArgs* /*e*/)
{

    NetworkInterface* adapters[] = NetworkInterface::GetAllNetworkInterfaces();
    System::Collections::IEnumerator* myEnum = adapters->GetEnumerator();
    while (myEnum->MoveNext())
    {
        NetworkInterface* n = __try_cast<NetworkInterface*>(myEnum->Current);
        Console::WriteLine(S"   {0} is {1}", n->Name, __box(n->OperationalStatus));
    }
}

int main()
{
    NetworkChange::NetworkAddressChanged += new 
        NetworkAddressChangedEventHandler(AddressChangedCallback);
    Console::WriteLine(S"Listening for address changes. Press any key to exit.");
    Console::ReadLine();
}

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

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

.NET Framework

Supported in: 3.5, 3.0, 2.0
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