XmlLinkedNode Class

Represents a node in the XML DOM that can be linked to other nodes.

Namespace: System.Xml

Assembly: System.Xml.dll

Inheritance

Object

XmlNode

XmlLinkedNode

Syntax

public abstract class XmlLinkedNode : XmlNode

Remarks

The XmlLinkedNode class is an abstract base class from which all nodes in the XML Document Object Model (DOM) that can be part of a linked list derive. This includes nodes such as XmlAttribute, XmlCDataSection, XmlComment, XmlDeclaration, XmlDocumentType, XmlElement, XmlEntity, XmlEntityReference, XmlIgnoredNamespaces, XmlNameTable, XmlNamespaceManager, XmlNotation, XmlProcessingInstruction, XmlSignificantWhitespace, XmlText, and XmlWhitespace. The linking mechanism allows for efficient traversal and manipulation of the XML tree structure.

This class provides properties for accessing the next and previous sibling nodes, facilitating operations like inserting, deleting, or reordering nodes within the DOM tree.

Properties

• NextSibling

  Gets the node immediately following this node.

  Return Value

  An XmlLinkedNode representing the next sibling node, or null if there is no next sibling.
• PreviousSibling

  Gets the node immediately preceding this node.

  Return Value

  An XmlLinkedNode representing the previous sibling node, or null if there is no previous sibling.

Methods

• AppendChild(XmlNode newChild)

  Appends the specified node to the end of the list of children of this node.

  Parameters

  newChild

  The XmlNode to append.

  Return Value

  The appended XmlNode. Returns null if the operation fails.
• InsertAfter(XmlNode newChild, XmlNode refChild)

  Inserts the specified node immediately after the specified reference node.

  Parameters

  newChild

  The XmlNode to insert.

  refChild

  The XmlNode that is the reference node. The newChild is inserted after this node.

  Return Value

  The inserted XmlNode. Returns null if the operation fails.
• InsertBefore(XmlNode newChild, XmlNode refChild)

  Inserts the specified node immediately before the specified reference node.

  Parameters

  newChild

  The XmlNode to insert.

  refChild

  The XmlNode that is the reference node. The newChild is inserted before this node.

  Return Value

  The inserted XmlNode. Returns null if the operation fails.
• RemoveChild(XmlNode oldChild)

  Removes the specified node from the list of children of this node.

  Parameters

  oldChild

  The XmlNode to remove.

  Return Value

  The removed XmlNode. Returns null if the operation fails.
• ReplaceChild(XmlNode newChild, XmlNode oldChild)

  Replaces the specified node with the specified new node.

  Parameters

  newChild

  The XmlNode to replace the existing node with.

  oldChild

  The XmlNode to replace.

  Return Value

  The node that was replaced. Returns null if the operation fails.

Examples

The following example demonstrates how to use the InsertAfter method to insert a new element into an existing XML document.

using System;
using System.Xml;

public class XmlLinkedNodeExample
{
    public static void Main(string[] args)
    {
        XmlDocument doc = new XmlDocument();
        doc.LoadXml("<catalog>" +
                    "  <book id='bk101'>" +
                    "    <author>Gambardella, Matthew</author>" +
                    "    <title>XML Developer's Guide</title>" +
                    "    <genre>Computer</genre>" +
                    "    <price>44.95</price>" +
                    "    <publish_date>2000-10-01</publish_date>" +
                    "    <description>An in-depth look at creating applications with XML.</description>" +
                    "  </book>" +
                    "  <book id='bk102'>" +
                    "    <author>Ralls, Kim</author>" +
                    "    <title>Midnight Rain</title>" +
                    "    <genre>Fantasy</genre>" +
                    "    <price>5.95</price>" +
                    "    <publish_date>2000-12-16</publish_date>" +
                    "    <description>A former architect battles corporate zombies, an evil sorceress, and her own childhood to become queen of the world.</description>" +
                    "  </book>" +
                    "</catalog>");

        XmlNode book1 = doc.SelectSingleNode("//book[@id='bk101']");
        XmlNode authorNode = book1.SelectSingleNode("author");

        // Create a new book element
        XmlElement newBook = doc.CreateElement("book");
        newBook.SetAttribute("id", "bk103");
        newBook.InnerXml = "<author>New Author</author>" +
                           "<title>New Title</title>" +
                           "<genre>Fiction</genre>" +
                           "<price>19.99</price>" +
                           "<publish_date>2023-01-01</publish_date>" +
                           "<description>A captivating new story.</description>";

        // Insert the new book after the first book
        if (book1 != null && authorNode != null)
        {
            // Using InsertAfter with a reference node
            // book1.InsertAfter(newBook, authorNode); // Incorrect - InsertAfter is on the parent node

            // Correct usage: insert after the first book node itself
            XmlNode catalogNode = doc.SelectSingleNode("catalog");
            catalogNode.InsertAfter(newBook, book1);

            Console.WriteLine("New book inserted successfully.");
            Console.WriteLine(doc.OuterXml);
        }
        else
        {
            Console.WriteLine("Could not find the reference book node.");
        }
    }
}