XmlNode.InsertBefore(XmlNode, XmlNode) Method

Definition

Namespace:

System.Xml

Assembly:

System.Xml.ReaderWriter.dll

Source:

XmlNode.cs

Inserts the specified node immediately before the specified reference node.

public:
 virtual System::Xml::XmlNode ^ InsertBefore(System::Xml::XmlNode ^ newChild, System::Xml::XmlNode ^ refChild);

public virtual System.Xml.XmlNode? InsertBefore (System.Xml.XmlNode newChild, System.Xml.XmlNode? refChild);

abstract member InsertBefore : System.Xml.XmlNode * System.Xml.XmlNode -> System.Xml.XmlNode
override this.InsertBefore : System.Xml.XmlNode * System.Xml.XmlNode -> System.Xml.XmlNode

Public Overridable Function InsertBefore (newChild As XmlNode, refChild As XmlNode) As XmlNode

Parameters

newChild

XmlNode

The node to insert.

refChild

XmlNode

The reference node. newChild is placed before this node.

Returns

XmlNode

The node being inserted.

Exceptions

InvalidOperationException

The current node is of a type that does not allow child nodes of the type of the newChild node.

The newChild is an ancestor of this node.

ArgumentException

The newChild was created from a different document than the one that created this node.

The refChild is not a child of this node.

This node is read-only.

Examples

The following example adds a new node to the XML document.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   XmlDocument^ doc = gcnew XmlDocument;
   doc->LoadXml( "<book genre='novel' ISBN='1-861001-57-5'>"
   "<title>Pride And Prejudice</title>"
   "</book>" );
   XmlNode^ root = doc->DocumentElement;
   
   //Create a new node.
   XmlElement^ elem = doc->CreateElement( "price" );
   elem->InnerText = "19.95";
   
   //Add the node to the document.
   root->InsertBefore( elem, root->FirstChild );
   Console::WriteLine( "Display the modified XML..." );
   doc->Save( Console::Out );
}

using System;
using System.IO;
using System.Xml;

public class Sample {

  public static void Main() {

    XmlDocument doc = new XmlDocument();
    doc.LoadXml("<book genre='novel' ISBN='1-861001-57-5'>" +
                "<title>Pride And Prejudice</title>" +
                "</book>");

    XmlNode root = doc.DocumentElement;

    //Create a new node.
    XmlElement elem = doc.CreateElement("price");
    elem.InnerText="19.95";

    //Add the node to the document.
    root.InsertBefore(elem, root.FirstChild);

    Console.WriteLine("Display the modified XML...");
    doc.Save(Console.Out);
  }
}

Option Strict
Option Explicit

Imports System.IO
Imports System.Xml

Public Class Sample
    
    Public Shared Sub Main()
        
        Dim doc As New XmlDocument()
        doc.LoadXml("<book genre='novel' ISBN='1-861001-57-5'>" & _
                    "<title>Pride And Prejudice</title>" & _
                    "</book>")
        
        Dim root As XmlNode = doc.DocumentElement
        
        'Create a new node.
        Dim elem As XmlElement = doc.CreateElement("price")
        elem.InnerText = "19.95"
        
        'Add the node to the document.
        root.InsertBefore(elem, root.FirstChild)
        
        Console.WriteLine("Display the modified XML...")
        doc.Save(Console.Out)
    End Sub
End Class

Remarks

If refChild is null, insert newChild at the end of the list of child nodes. All the contents of the newChild are inserted, in the same order, before refChild. If the newChild is already in the tree, it is removed from its original position and added to its target position. For more information about inserting nodes, see Inserting Nodes into an XML Document.

If the node being inserted was created from another document, you can use XmlDocument.ImportNode to import the node to the current document. The imported node can then be inserted into the current document.

Notes to Inheritors

When overriding InsertBefore in a derived class, in order for events to be raised correctly, you must call the InsertBefore method of the base class.

See also

• ImportNode(XmlNode, Boolean)
• Inserting Nodes into an XML Document