如何使用。net XML序列化将对象序列化为单个值

Assuming I have the following:

假设我有以下几点:

[Serializable]
public class Foo
{
    public Bar bar
    {
        get;
        set;
    }

    public Ram ram
    {
        get;
        set;
    }
}

[Serializable]
public class Bar
{
    [XmlElement("barId")]
    public int Id
    {
        get;
        set;
    }
}

[Serializable]
public class Ram
{
    [XmlElement("ramId")]
    public int RamId
    {
        get;
        set;
    }
}
[S