Determine the size of object without its virtual table pointers

问题

Is there a generic way (not platform dependent) to get at compile time the size of a class object in the memory, without counting the vtable pointers?

回答1:

As you are asking for a portable way:

class MyClass
{
private:
  struct S 
  {
    DataMemberType1 dataMember1;
    ...
    DataMemberTypeN dataMemberN;
  } m;

public:
  static const size_t MemberSize = sizeof(S);
}; 

回答2:

Use sizeof on this class, it doesn't include size of the vtable just the pointer.

来源：https://stackoverflow.com/questions/28433973/determine-the-size-of-object-without-its-virtual-table-pointers