Question

I wanna xml serialize a custom object that contains other custom objects. I do it like below but it wont work.

class A()
{
public B b;
}

class B()
{
public int a;
}

System.Xml.Serialization.XmlSerializer writer = new System.Xml.Serialization.XmlSerializer(typeof(A));  
XmlAttributes xmlAttributes = new XmlAttributes();   
System.IO.StreamWriter file = new System.IO.StreamWriter(   @"d:\SerializationOverview.xml");
writer.Serialize(file, new A());  
file.Close();

the result is:

<A>
</A>

Answer 1

Firstly, both A and B need to be marked public.

The new A() has not got a value in b to serialize; it doesn’t serialize nulls. Give it a value:

writer.Serialize(file, new A { b = new B { a = 123 } });

Also: try to prefer properties over public fields.

For example:

using System.IO;
using System.Xml.Serialization;
public class A
{
    public B B { get; set; }
}
public class B
{
    public int A {get;set;}
}
static class Program
{
    static void Main()
    {
        var writer = new XmlSerializer(typeof(A));
        using (var file = File.Create(@"SerializationOverview.xml"))
        {
            writer.Serialize(file, new A { B = new B { A = 123 } });
        }
    }
}