XmlNodeChangedEventHandler Delegate
Represents the method that handles NodeChanged, NodeChanging, NodeInserted, NodeInserting, NodeRemoved and NodeRemoving events.
Assembly: System.Xml (in System.Xml.dll)
'Declaration Public Delegate Sub XmlNodeChangedEventHandler ( _ sender As Object, _ e As XmlNodeChangedEventArgs _ )
Parameters
- sender
- Type: System.Object
The source of the event.
- e
- Type: System.Xml.XmlNodeChangedEventArgs
An XmlNodeChangedEventArgs containing the event data.
When you create an XmlNodeChangedEventHandler delegate, you identify the method that handles the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Events and Delegates.
The following example shows how to handle the NodeChanged and NodeInserted events.
Imports System Imports System.IO Imports System.Xml Namespace Microsoft.Samples.Xml Public Class Sample Private Const filename As String = "book.xml" Public Shared Sub Main() Dim mySample As Sample = New Sample() mySample.Run(filename) End Sub Public Sub Run(ByVal args As String) ' Create and load the XML document. Console.WriteLine("Loading file {0} ...", args) Dim doc As XmlDocument = New XmlDocument() doc.Load(args) 'Create the event handlers. AddHandler doc.NodeChanged, AddressOf MyNodeChangedEvent AddHandler doc.NodeInserted, AddressOf MyNodeInsertedEvent ' Change the book price. doc.DocumentElement.LastChild.InnerText = "5.95" ' Add a new element. Dim newElem As XmlElement = doc.CreateElement("style") newElem.InnerText = "hardcover" doc.DocumentElement.AppendChild(newElem) Console.WriteLine() Console.WriteLine("Display the modified XML...") Console.WriteLine(doc.OuterXml) End Sub ' Handle the NodeChanged event. Private Sub MyNodeChangedEvent(ByVal source As Object, ByVal args As XmlNodeChangedEventArgs) Console.Write("Node Changed Event: <{0}> changed", args.Node.Name) If Not (args.Node.Value Is Nothing) Then Console.WriteLine(" with value {0}", args.Node.Value) Else Console.WriteLine("") End If End Sub ' Handle the NodeInserted event. Private Sub MyNodeInsertedEvent(ByVal source As Object, ByVal args As XmlNodeChangedEventArgs) Console.Write("Node Inserted Event: <{0}> inserted", args.Node.Name) If Not (args.Node.Value Is Nothing) Then Console.WriteLine(" with value {0}", args.Node.Value) Else Console.WriteLine("") End If End Sub End Class End Namespace
The example uses the file book.xml as input.
<!--sample XML fragment--> <book genre='novel' ISBN='1-861003-78' misc='sale-item'> <title>The Handmaid's Tale</title> <price>14.95</price> </book>
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.