使用NHibernate.Mapping.Attributes

 [NHibernate.Mapping.Attributes.Id(0, TypeType=typeof(int))] // Don't put it after [ManyToOne] !!!
        [NHibernate.Mapping.Attributes.Generator(1, Class="uuid.hex")]
    [NHibernate.Mapping.Attributes.ManyToOne(2, ClassType=typeof(Foo), OuterJoin=OuterJoinStrategy.True)]
    private Foo Entity;

  <id type="Int32">
        <generator class="uuid.hex" />
    </id>
    <many-to-one name="Entity" class="Namespaces.Foo, SampleAssembly"
outer-join="true" />

 <p>
        <c>
            <x />
        </c>
        <x />
    </p>

 [Attributes.P(0)]
        [Attributes.C(1)]
            [Attributes.X(2)]
        [Attributes.X(3)]
    public MyType MyProperty;