如何跟踪扩展部分对象的变化。用一个自定义属性

I have a Class called Person which has the properties Name and Lastname. I have created a partial class Person which extends the EF generated one with a FullName property. In a certain moment I need to generate the Fullname. The fullname is binded to a control so it can be shown. If I change the fullname property, the wpf control does not get updated. I have a Class called Person which has the prop