read and write xml file in c#

How to Read and Write XML File in C#

In C#, working with XML files is convenient using the classes available in the System.Xml namespace. Whether you're handling configuration files, data exchange, or custom data storage, XML provides a versatile way to manage structured data. This article explains how to read and write XML files in C# using practical examples.

Reading an XML File

Example: Reading XML with XmlDocument

The XmlDocument class provides a way to load, navigate, and extract data from XML files.

using System;
using System.Xml;

public class XmlReadExample
{
    public static void Main()
    {
        // Path to the XML file
        string filePath = "library.xml";

        // Load the XML file into an XmlDocument
        XmlDocument doc = new XmlDocument();
        doc.Load(filePath);

        // Access nodes using XPath
        XmlNodeList bookNodes = doc.SelectNodes("//book");

        Console.WriteLine("Books in the Library:");
        foreach (XmlNode book in bookNodes)
        {
            string title = book["title"]?.InnerText;
            string author = book["author"]?.InnerText;
            string year = book["year"]?.InnerText;

            Console.WriteLine($"Title: {title}, Author: {author}, Year: {year}");
        }
    }
}

Tips for Reading XML Files

• XPath Expressions: Use XPath expressions like //book to navigate through elements efficiently.
• Exception Handling: Use try-catch blocks to handle potential file errors gracefully.

Writing to an XML File

Example: Writing XML with XmlWriter

To write XML data to a file, the XmlWriter class provides a flexible way to generate XML content.

using System;
using System.Xml;

public class XmlWriteExample
{
    public static void Main()
    {
        // Path where the XML file will be created
        string filePath = "library.xml";

        // Set up XmlWriter settings
        XmlWriterSettings settings = new XmlWriterSettings
        {
            Indent = true,
            NewLineOnAttributes = false
        };

        // Create the XmlWriter object
        using (XmlWriter writer = XmlWriter.Create(filePath, settings))
        {
            // Start the document
            writer.WriteStartDocument();
            writer.WriteStartElement("library");

            // Write a book element
            writer.WriteStartElement("book");
            writer.WriteElementString("title", "To Kill a Mockingbird");
            writer.WriteElementString("author", "Harper Lee");
            writer.WriteElementString("year", "1960");
            writer.WriteEndElement(); // book

            writer.WriteEndElement(); // library
            writer.WriteEndDocument(); // End the document
        }

        Console.WriteLine($"XML document saved to {filePath}");
    }
}

Tips for Writing XML Files

• XmlWriterSettings: Customize indentation and new-line behavior using XmlWriterSettings.
• Well-Formed XML: Ensure that your XML is well-formed by correctly closing all tags.

Conclusion

In C#, reading and writing XML files is straightforward using the System.Xml namespace. By leveraging the XmlDocument and XmlWriter classes, you can handle structured data efficiently for any application.