XmlComment Class

Namespace: System.Xml
Assembly: System.Xml (in System.Xml.dll)

Represents a comment node in the XML document.

Inheritance

System.Object
System.Xml.XmlNode
System.Xml.XmlCharacterData
System.Xml.XmlCDataSection
System.Xml.XmlComment

Syntax

public class XmlComment : XmlCharacterData

Remarks

An XmlComment node is used to store comments in an XML document. Comments are ignored by the XML parser but can be read by applications. This class provides methods to create and manipulate comment nodes within an XmlDocument.

Constructors

XmlComment(string data, XmlDocument doc)

public XmlComment (string data, XmlDocument doc);

Initializes a new instance of the XmlComment class.

data: The content of the comment. This value is typically a string.
doc: The XmlDocument to which the comment will be added.

Properties

Name	Description
`BaseURI`	Gets the base URI of the current node.
`ChildNodes`	Gets a `XmlNodeList` containing the children of this node. For `XmlComment`, this will always be an empty list.
`Data`	Gets or sets the value of this node. For an `XmlComment`, this is the text content of the comment.
`DocumentType`	Gets the `XmlDocument` to which this node belongs.
`FirstChild`	Gets the first child of this node. For `XmlComment`, this is always `null`.
`InnerXml`	Gets or sets a value indicating whether the node is read-only. `XmlComment` nodes are generally mutable unless the document itself is read-only.
`IsReadOnly`	Gets a value indicating whether the node is read-only. `XmlComment` nodes are generally mutable unless the document itself is read-only.
`LastChild`	Gets the last child of this node. For `XmlComment`, this is always `null`.
`LocalName`	Gets the local name of the node. For `XmlComment`, this is always `#comment`.
`Name`	Gets the qualified name of the node. For `XmlComment`, this is always `#comment`.
`NextSibling`	Gets the node immediately following this node.
`NodeType`	Gets the type of the current node. Returns `XmlNodeType.Comment`.
`OuterXml`	Gets the markup representing this node and all its children. For an `XmlComment`, this will be the comment markup (e.g., `<!-- My comment -->`).
`OwnerDocument`	Gets the `XmlDocument` associated with this node.
`ParentNode`	Gets the parent of this node (`XmlDocument` or another `XmlNode`).
`Prefix`	Gets the namespace prefix of this node. For `XmlComment`, this is always an empty string.
`PreviousSibling`	Gets the node immediately preceding this node.
`Value`	Gets or sets the text content of the comment.

Methods

Name	Description
`CloneNode(bool deep)`	Creates a copy of this node. If `deep` is true, also copies all the children of the node. For `XmlComment`, the `deep` parameter has no effect as comments have no children.
`AppendChild(XmlNode newChild)`	Appends the specified node to the end of the list of children of this node. This method throws an exception for `XmlComment` as it cannot have children.
`InsertAfter(XmlNode newChild, XmlNode refChild)`	Inserts the specified node after the specified reference node. This method throws an exception for `XmlComment` as it cannot have children.
`InsertBefore(XmlNode newChild, XmlNode refChild)`	Inserts the specified node before the specified reference node. This method throws an exception for `XmlComment` as it cannot have children.
`Normalize()`	Ensures that all the nodes in the subtree are in a "normal" form, that is, that there are no empty text nodes and that the nodes are maximally merged. For `XmlComment`, this operation typically has no visible effect.
`RemoveAll()`	Removes all the children of this node. This method throws an exception for `XmlComment` as it cannot have children.
`RemoveChild(XmlNode oldChild)`	Removes the specified child node. This method throws an exception for `XmlComment` as it cannot have children.
`ReplaceChild(XmlNode newChild, XmlNode oldChild)`	Replaces the child node `oldChild` with `newChild`. This method throws an exception for `XmlComment` as it cannot have children.
`WriteTo(XmlWriter w)`	Saves the current node to the specified `XmlWriter`.

Example

The following C# example demonstrates how to create an XmlDocument, add a comment to it, and then write the document to the console.

using System;
using System.Xml;

public class Example
{
    public static void Main(string[] args)
    {
        // Create a new XmlDocument
        XmlDocument doc = new XmlDocument();

        // Create an XML declaration node
        XmlDeclaration xmlDeclaration = doc.CreateXmlDeclaration("1.0", "utf-8", null);
        doc.AppendChild(xmlDeclaration);

        // Create a root element
        XmlElement root = doc.CreateElement("root");
        doc.AppendChild(root);

        // Create an XmlComment node
        XmlComment comment = doc.CreateComment("This is a sample comment.");
        root.AppendChild(comment);

        // Create another element
        XmlElement element = doc.CreateElement("item");
        element.InnerText = "Some data";
        root.AppendChild(element);

        // Save the document to the console
        Console.WriteLine(doc.OuterXml);
    }
}

Output:

<?xml version="1.0" encoding="utf-8"?>
<root><!--This is a sample comment.--><item>Some data</item></root>

MSDN Documentation