多态——动态绑定

写出下面程序的输出结果

class A{public: void FuncA() {     printf( "FuncA called\n" ); } virtual void FuncB() {     printf( "FuncB called\n" ); }};class B : public A{public: void FuncA() {     A::FuncA();     printf( "FuncAB called\n" ); } virtual void FuncB() {     printf( "FuncBB called\n" ); }};void main( void ){ B  b; A  *pa; pa = &b; A *pa2 = new A; pa->FuncA();  pa->FuncB();  pa2->FuncA();  pa2->FuncB(); delete pa2;}

解题思路：

B  b; 

A  *pa;

pa = &b;

A *pa2 = newA;

pa->FuncA(); //pa=&b动态绑定但是FuncA不是虚函数，所以FuncA called

pa->FuncB(); //FuncB是虚函数所以调用B中FuncB，FuncBB called  

pa2->FuncA(); //pa2是A类指针，不涉及虚函数，调用的都是A中函数，所以FuncA called FuncB called

pa2->FuncB()