System.Xml Assembly

The System.Xml namespace provides standards-based support for processing XML. This includes classes for reading, writing, and manipulating XML documents and streams. It supports XML 1.0, XPath, XSLT, and the Document Object Model (DOM) and offers a fast, forward-only stream-based approach through XmlReader and XmlWriter.

Key Namespaces

• System.Xml.Linq - Provides LINQ to XML capabilities.
• System.Xml.Serialization - Classes for XML serialization.
• System.Xml.XPath - Classes for evaluating XPath expressions.
• System.Xml.Xsl - Classes for transforming XML documents using XSLT.

Core Classes

• XmlReader - Provides a fast, forward-only, forward-read-only way to read a stream of XML data.
• XmlWriter - Provides a fast, forward-only, forward-write-only way to write XML data.
• XmlDocument - Represents an XML document in memory as a traversable tree structure (DOM).
• XElement - Represents an XML element in LINQ to XML.
• XPathNavigator - Navigates to nodes in an XML document.
• XslTransform - Transforms an XML document using an XSLT stylesheet.

Example Usage

Reading XML with XmlReader

This example demonstrates how to read an XML file using XmlReader:

using System;
using System.Xml;

public class XmlReaderExample
{
    public static void Main(string[] args)
    {
        string xmlString = "<bookstore><book genre=\"fiction\"><title lang=\"en\">The Great Gatsby</title><author>F. Scott Fitzgerald</author></book></bookstore>";

        using (XmlReader reader = XmlReader.Create(new System.IO.StringReader(xmlString)))
        {
            while (reader.Read())
            {
                switch (reader.NodeType)
                {
                    case XmlNodeType.Element:
                        Console.Write($"<{reader.Name}>");
                        if (reader.HasAttributes)
                        {
                            while (reader.MoveToNextAttribute())
                            {
                                Console.Write($" {reader.Name}='{reader.Value}'");
                            }
                            reader.MoveToElement();
                        }
                        Console.WriteLine();
                        break;
                    case XmlNodeType.Text:
                        Console.WriteLine($"  {reader.Value}");
                        break;
                    case XmlNodeType.XmlDeclaration:
                    case XmlNodeType.ProcessingInstruction:
                        Console.WriteLine($"<?{reader.Name} {reader.Value}?>");
                        break;
                    case XmlNodeType.Comment:
                        Console.WriteLine($"<!-- {reader.Value} -->");
                        break;
                    case XmlNodeType.EndElement:
                        Console.WriteLine($"</{reader.Name}>");
                        break;
                }
            }
        }
    }
}
        

Further Information

This documentation pertains to assemblies commonly found in the .NET Framework and .NET Core/.NET 5+ ecosystems. Specific class availability and behavior may vary slightly between different versions.