.NET XmlSerializer错误，当两个类具有相同名称的属性时

public class Barn
{
    public Horse Horse { get; set; }
    public Motorcycle Motorcycle { get; set; }
}

public class Horse
{
    public Horse()
    {
        Rider = \"Jim Craig\";
    }

    [XmlElement(IsNullable = true, Namespace = \"abc\")]
    public string Rider { get; set; }
}

public class Motorcycle
{
    public Motorcycle()
    {
        Rider = \"Ghost\";
    }

    [XmlElement(IsNullable = false, Namespace = \"abc\")]
    public string Rider { get; set; }
}

// Create a Barn, with a Horse, with a null Rider
Barn barnBefore = new Barn();
barnBefore.Horse = new Horse();
barnBefore.Horse.Rider = null;

// Serialize and then deserialize the Barn
XmlSerializer serializer = new XmlSerializer(typeof(Barn));
MemoryStream stream = new MemoryStream();
serializer.Serialize(stream, barnBefore);
stream.Seek(0, SeekOrigin.Begin);
Barn barnAfter = (Barn)serializer.Deserialize(stream);

// Is the Horse\'s Rider still null?
Console.WriteLine(barnAfter.Horse.Rider == null ? \"null\" : \"not null\");

Horse

Rider

IsNullable = true

Barn

Horse

Motorcycle

Motorcycle

Rider

string

XmlSerializer