++前置和后置重载运算符函数 

 1 #include <iostream>
 2 using namespace std;
 3 
 4 class Increase
 5 {
 6 public:
 7         Increase() { value = 0; }
 8         void display() const { cout << value << endl;}; 
 9 
10         Increase operator ++ ();  // 前置 ++ 的重载函数（成员函数）
11         Increase operator ++ (int); // 后置 ++  的重载函数（成员函数）
12 
13 private:
14         unsigned value;
15 };
16 
17 Increase Increase :: operator ++()
18 {
19         value++;
20         return *this;
21 }
22 
23 Increase Increase :: operator ++(int)
24 {
25         Increase temp; 
26         //temp.value = value++;     // 相当于下面两句
27         temp.value = value;         // 保存为改变的前的值
28         this->value = value + 1;
29         return temp;
30 }
31 
32 int main()
33 {
34         Increase a, b, n, m;
35         for ( int i = 0; i < 10; i++)
36                 a = n++;
37         cout << "n = ";
38         n.display(); // n = 10
39         cout << "a = ";
40         a.display(); // a = 9
41                 
42         for( int i = 0; i < 10; i++)
43                 b = ++m; 
44         cout << "m = "; // 10 
45         n.display();
46         cout << "b = "; // 10
47         b.display();
48 
49         return 0;
50 }

 

posted on 2016-09-09 15:15  youngqqcn  阅读(1129)  评论(0)    收藏  举报