articles » current » dot-net » add-comment-to-xml-document

.NET: Add Comment to XML Document

Use the XmlSerializer and XmlDocument classes to add a comment to XML files

First, learn how to use the .NET XmlSerializer class.

To add a comment to XML using the XmlSerializer and XmlDocument classes, create a class that inherits from StringWriter and overrides the Encoding to make it UTF-8 as this is typical for XML. Next, create a XmlSerializer then serialize a class and load the serialized data into a new XmlDocument, create a new comment (XmlComment) insert it into the document (the XML document element in this example) and then save the document to an new StringWriterUtf8.

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Xml;
using System.Xml.Serialization;

namespace XmlExample
{
	public class StringWriterUtf8 : StringWriter
	{
		public override Encoding Encoding => Encoding.UTF8;
	}

	[Serializable]
	[XmlRoot("node")]
	[XmlType("node")]
	public class Node
	{
		[XmlElement("name")]
		public string Name { get; set; }

	}

	[Serializable]
	[XmlRoot(ElementName = "foobar", Namespace = "")]
	public class FooBar : List<Node>
	{
		public string ToXml()
		{
			var serializer = new XmlSerializer(typeof(FooBar));

			using (var writer = new StringWriterUtf8())
			{
				serializer.Serialize(writer, this);

				XmlDocument doc = new XmlDocument();
				doc.LoadXml(writer.ToString());

				XmlComment newComment;
				newComment = doc.CreateComment("  This comment added by prowaretech.com  ");

				XmlElement root = doc.DocumentElement;
				doc.InsertBefore(newComment, root);

				using (var sr = new StringWriterUtf8())
				{
					doc.Save(sr);
					return sr.ToString();
				}
			}
		}

	}
}

Using the above example:

using System;
using System.IO;

namespace ConsoleApp1
{
	class Program
	{
		static void Main(string[] args)
		{
			var fb = new XmlExample.FooBar();
			fb.Add(new XmlExample.Node { Name = "Node1" });
			Console.Write(fb.ToXml());
		}
	}
}

The output should look like this:

<?xml version="1.0" encoding="utf-8"?>
<!--  This comment added by prowaretech.com  -->
<foobar xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <node>
    <name>Node1</name>
  </node>
</foobar>

Coding Video

https://youtu.be/HG8VOxTv5sI


This site uses cookies. Cookies are simple text files stored on the user's computer. They are used for adding features and security to this site. Read the privacy policy.
CLOSE