每个对象都有一些附加字节，通用语言运行库用来管理对象，如对象的虚表指针和同步锁定引用。

Every object has some additional bytes that the common language runtime USES to manage the object, such as the object's virtual table pointer and a reference to a sync block.

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有一个为每个类的虚表，其中包含每个成员的功能的实现的指针列表。

There's a virtual table for each class, which contains a list of Pointers to the implementation of each member function.

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