道有关继承类
大小问题
起来看下吧:#
<iostream> using
std; struct A{
virtual
fun
; //4 
char x; //1
};
struct B:public A{
myfun; //2 不占类B空间 union{
unsigned
m; unsigned
c; }xx; //4
(__stdcall *funs); //4 };
union{
unsigned
m; unsigned
c; }xx;
myfun; (__stdcall *funs); //4 struct C{
myfun; //2 union{
unsigned
m; unsigned
c; }xx; //4
(__stdcall *funs); //4 };
{
//cout<<endl;
//cout<<off
of( B , x )<<endl; //cout<<off
of( B , xx )<<endl; //cout<<off
of( B , funs )<<endl; cout < <
(myfun) < < endl;//2 cout < <
(( *funs)) < < endl;//4 cout < <
(xx) < < endl;//4 cout < <
(A) < < endl;//8 cout < <
(B) < < endl;//16 cout < <
(C) < < endl;//8 
0; }
//为啥
(B)是16而不是18？？offof可以看偏移 //看深入探索C
对象模型类中非虚
不占空间 
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