NetworkChange Class
Allows applications to receive notification when the Internet Protocol (IP) address of a network interface, also called a network card or adapter, changes.
Assembly: System (in System.dll)
The NetworkChange type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | NetworkAddressChanged | Occurs when the IP address of a network interface changes. |
![]() ![]() | NetworkAvailabilityChanged | Occurs when the availability of the network changes. |
The NetworkChange class provides address change notification by raising NetworkAddressChanged events. An interface address can change for many reasons, such as a disconnected network cable, moving out of range of a wireless Local Area Network, or hardware failure.
To receive notification, you must identify your application's event handlers, which are one or more methods that perform your application-specific tasks each time the event is raised. To have a NetworkChange object call your event-handling methods when a NetworkAddressChanged event occurs, you must associate the methods with a NetworkAddressChangedEventHandler delegate, and add this delegate to the event.
The following code example listens for address changes and displays the status of network interfaces when a NetworkAddressChanged event occurs.
#using <System.dll> using namespace System; using namespace System::Net; using namespace System::Net::NetworkInformation; void AddressChangedCallback( Object^ /*sender*/, EventArgs^ /*e*/ ) { array<NetworkInterface^>^adapters = NetworkInterface::GetAllNetworkInterfaces(); System::Collections::IEnumerator^ myEnum = adapters->GetEnumerator(); while ( myEnum->MoveNext() ) { NetworkInterface^ n = safe_cast<NetworkInterface^>(myEnum->Current); Console::WriteLine( " {0} is {1}", n->Name, n->OperationalStatus ); } } int main() { NetworkChange::NetworkAddressChanged += gcnew NetworkAddressChangedEventHandler( AddressChangedCallback ); Console::WriteLine( "Listening for address changes. Press any key to exit." ); Console::ReadLine(); }
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

