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.

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

System.Object
  System.Net.NetworkInformation.NetworkChange

Public Class NetworkChange

NameDescription
System_CAPS_pubmethodNetworkChange()

Obsolete.Initializes a new instance of the NetworkChange class.

NameDescription
System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_protmethodFinalize()

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_protmethodMemberwiseClone()

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethodSystem_CAPS_staticRegisterNetworkChange(NetworkChange)

Obsolete.Registers a network change instance to receive network change events.

System_CAPS_pubmethodToString()

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubeventSystem_CAPS_staticNetworkAddressChanged

Occurs when the IP address of a network interface changes.

System_CAPS_pubeventSystem_CAPS_staticNetworkAvailabilityChanged

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.

Imports System
Imports System.Net
Imports System.Net.NetworkInformation

Public Class NetworkingExample
    Public Shared Sub Main()
        AddHandler NetworkChange.NetworkAddressChanged, AddressOf AddressChangedCallback
        Console.WriteLine("Listening for address changes. Press any key to exit.")
        Console.ReadLine()
    End Sub 'Main
    Private Shared Sub AddressChangedCallback(ByVal sender As Object, ByVal e As EventArgs)

        Dim adapters As NetworkInterface() = NetworkInterface.GetAllNetworkInterfaces()
        Dim n As NetworkInterface
        For Each n In adapters
            Console.WriteLine("   {0} is {1}", n.Name, n.OperationalStatus)
        Next n
    End Sub
End Class

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 3.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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