17-1.txt

《C/C++完美演绎》源代码

/* 范例：17-1 */
#include <iostream.h>

class A
{
  public:
    A(){a=1;} 	// 以class A 建立的对象初值都设a=1
    int a;
};

class B:public A
{
  public:
    B(){b=2;}	// 以class B 建立的对象初值都设b=2
    int b;
};

void main()
{
  A objA;
  B objB;

  cout << "sizeof(objA) = " << sizeof(objA) << "\n";
  cout << "sizeof(objB) = " << sizeof(objB) << "\n";

  /* 观察objA与objB对象,成员地址 */
  cout << &objA << " " << &objA.a << "\n";
  cout << &objB << " " << &objB.a << " " << &objB.b << "\n";
  cout << objA.a << "\n";
  cout << objB.a << " " << objB.b << "\n";

  getchar();
}

程序执行结果：
sizeof(objA) = 4
sizeof(objB) = 8
0065FE00 0065FE00
0065FDF8 0065FDF8 0065FDFC
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