Use Visual C# to serialize an object to XML

Article
05/08/2022

This article provides a method about how to serialize an object to Extensible Markup Language (XML) by using Visual C#.

Original product version: Visual Studio
Original KB number: 815813

Summary

The method described in this article is useful for persisting the state of an object. The method is also useful for cloning an object by de-serializing the XML back to a new object.

This article refers to the following Microsoft .NET Framework Class Library namespaces:

System.Xml
System.Xml.Serialization

Requirements

This article assumes that you're familiar with the following topics:

Visual Studio
General familiarity with XML
General familiarity with Visual C#

XML serialization

Serialization is the process of taking the state of an object and persisting it in some fashion. The .NET Framework includes powerful objects that can serialize any object to XML. The System.Xml.Serialization namespace provides this capability.

Follow these steps to create a console application that creates an object, and then serializes its state to XML:

In Visual C#, create a new Console Application project.
On the Project menu, select Add Class to add a new class to the project.
In the Add New Item dialog box, change the name of the class to clsPerson.
Select Add. A new class is created.

Add the following code after the public class clsPerson statement.

public string FirstName;
public string MI;
public string LastName;

Switch to the code window for Program.cs in Visual Studio.
In the void Main method, declare and create an instance of the clsPerson class:
```
clsPerson p = new clsPerson();
```

Set the properties of the clsPerson object:

p.FirstName = "Jeff";
p.MI = "A";
p.LastName = "Price";

The Xml.Serialization namespace contains an XmlSerializer class that serializes an object to XML. When you create an instance of XmlSerializer, you pass the type of the class that you want to serialize into its constructor:
```
System.Xml.Serialization.XmlSerializer x = new System.Xml.Serialization.XmlSerializer(p.GetType());
```
The Serialize method is used to serialize an object to XML. Serialize is overloaded and can send output to a TextWriter, Stream, or XMLWriter object. In this example, you send the output to the console:
```
x.Serialize(Console.Out,p);
Console.WriteLine();
Console.ReadLine();
```

Complete code listing

using System;

public class clsPerson
{
    public  string FirstName;
    public  string MI;
    public  string LastName;
}

class class1
{
    static void Main(string[] args)
    {
        clsPerson p=new clsPerson();
        p.FirstName = "Jeff";
        p.MI = "A";
        p.LastName = "Price";
        System.Xml.Serialization.XmlSerializer x = new System.Xml.Serialization.XmlSerializer(p.GetType());
        x.Serialize(Console.Out, p);
        Console.WriteLine();
        Console.ReadLine();
    }
}

Verification

To verify that your project works, press CTRL+F5 to run the project. A clsPerson object is created and populated with the values that you entered. This state is serialized to XML. The console window shows the following code:

<?xml version="1.0" encoding="IBM437"?>
<clsPerson xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
    <FirstName>Jeff</FirstName>
    <MI>A</MI>
    <LastName>Price</LastName>
</clsPerson>

Troubleshoot

The Xml.Serialization.XmlSerializer object performs only shallow serialization. If you also want to serialize the private variables of an object or child objects, you must use deep serialization.