C++類成員函數指針

使用類成員函數指針需要掌握的三點。
1) 申明類成員函數指針：::*
2) 通過對象指針調用類函數指針：->*
3) 通過對象調用類函數指針：.*

例：

1. /** 定義基類和子類 **/
2. class Base {
3. public:
4. virtual void print1() {
5. std::cout << "Base::print1()" << std::endl;
6. }
9. virtual void print2() {
10. std::cout << "Base::print2()" << std::endl;
11. }
12. };
15. class Derived : public Base {
16. public:
17. virtual void print1() {
18. std::cout << "Derived::print1()" << std::endl;
19. }
22. virtual void print2() {
23. std::cout << "Derived::print2()" << std::endl;
24. }
25. };
28. /** 申明類成員函數指針類型 **/
29. typedef void (Base::*fn)();
32. /** 通過對象指針調用類函數指針 **/
33. void test1(Base* obj, fn func) {
34. (obj->*func)();
35. }
38. /** 通過對象調用類函數指針 **/
39. void test2(Base& obj, fn func) {
40. (obj.*func)();
41. }
44. void test_function_pointer() {
45. Base b;
46. Derived d;
48. test1(&b, &Base::print1);
49. test1(&b, &Base::print2);
50. test1(&d, &Base::print1);
51. test1(&d, &Base::print2);
55. test2(b, &Base::print2);
56. test2(d, &Base::print2);
57. }