Introduction:

In C#, the XmlDocument class provides a powerful way to parse and manipulate XML documents. In this blog, we will explore the process of converting an XML string into an XmlDocument object using multiple methods.

Method 1: Using XmlDocument.Parse() Method

The XmlDocument class in C# offers a straightforward method called Parse() that allows us to convert an XML string into an XmlDocument object.

using System;
using System.Xml;

class Program
{
    static void Main()
    {
        string xmlString = "<root><element>Hello, XmlDocument!</element></root>";
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(xmlString);

        XmlNode root = xmlDoc.DocumentElement;
        Console.WriteLine("Method 1 Output:");
        Console.WriteLine(root.InnerText);
    }
}

Output:

Method 1 Output:
Hello, XmlDocument!

In this method, we start by creating an XmlDocument instance. We then use the LoadXml() method to load the XML string into the XmlDocument object. After loading, we can easily access and manipulate the XML data. In this case, we retrieve the text content of the "element" node using the InnerText property.

Method 2: Using XmlReader with XmlDocument

Another approach involves using the XmlReader class in conjunction with XmlDocument to convert an XML string. This approach can be advantageous when dealing with large XML files.

using System;
using System.Xml;

class Program
{
    static void Main()
    {
        string xmlString = "<root><element>Hello, XmlDocument with XmlReader!</element></root>";
        XmlDocument xmlDoc = new XmlDocument();

        using (XmlReader reader = XmlReader.Create(new System.IO.StringReader(xmlString)))
        {
            xmlDoc.Load(reader);
        }

        XmlNode root = xmlDoc.DocumentElement;
        Console.WriteLine("\nMethod 2 Output:");
        Console.WriteLine(root.InnerText);
    }
}

Output:

Method 2 Output:
Hello, XmlDocument with XmlReader!

In this method, we utilize the XmlReader class to efficiently read the XML data. We create an XmlReader instance using XmlReader.Create() and pass the XML string as input. Then, we load the XmlReader into the XmlDocument using the Load() method, similar to Method 1. This approach is especially useful for processing large XML files while minimizing memory usage.

Method 3: Using XmlSerializer to Deserialize

If your XML structure corresponds to a predefined class, you can use the XmlSerializer class to deserialize the XML string into an object.

using System;
using System.Xml;
using System.Xml.Serialization;

[XmlRoot("root")]
public class Data
{
    [XmlElement("element")]
    public string Element { get; set; }
}

class Program
{
    static void Main()
    {
        string xmlString = "<root><element>Hello, XmlDocument with XmlSerializer!</element></root>";

        XmlSerializer serializer = new XmlSerializer(typeof(Data));
        Data data;

        using (XmlReader reader = XmlReader.Create(new System.IO.StringReader(xmlString)))
        {
            data = (Data)serializer.Deserialize(reader);
        }

        Console.WriteLine("\nMethod 3 Output:");
        Console.WriteLine(data.Element);
    }
}

Output:

Method 3 Output:
Hello, XmlDocument with XmlSerializer!

In this method, we define a C# class named "Data" that mirrors the structure of the XML data using XmlRoot and XmlElement attributes. We then use the XmlSerializer class to deserialize the XML string into an instance of the "Data" class. This approach provides a structured and type-safe representation of the XML data, making it easy to work with.

Conclusion:

In this blog, we explored three different methods to convert XML strings into XmlDocument objects in C#. We started with the XmlDocument.Parse() method for straightforward conversion. Next, we learned how to use XmlReader with XmlDocument for efficient handling of larger XML files. Finally, we discovered how to use XmlSerializer for structured XML data deserialization into predefined classes.