c++ 重载运算符

要点
1 operator关键词 修饰运算符
2 跟函数重载类比

// 修饰 运算符 ()

1 #include <iostream>
  2 using namespace std;
  3 
  4 class Distance
  5 {
  6    private:
  7       int feet;             // 0 到无穷
  8       int inches;           // 0 到 12
  9    public:
 10       // 所需的构造函数
 11       Distance(){
 12          feet = 0;
 13          inches = 0;
 14       }
 15       Distance(int f, int i){
 16          feet = f;
 17          inches = i;
 18       }
 19       // 重载函数调用运算符
 20       Distance operator()(int a, int b, int c)
 21       {
 22          Distance D;
 23          // 进行随机计算
 24          D.feet = a + c + 10;
 25          D.inches = b + c + 100 ;
 26          return D;
 27       }
 28       // 显示距离的方法
 29       void displayDistance()
 30       {
 31          cout << "F: " << feet <<  " I:" <<  inches << endl;
 32       }
 33 
 34 };
 35 int main()
 36 {
 37    Distance D1(11, 10), D2;
 38 
 39    cout << "First Distance : ";
 40    D1.displayDistance();
 41 
 42    D2 = D1(10, 10, 10); // invoke operator()
 43    cout << "Second Distance :";
 44    D2.displayDistance();
 45 
 46    return 0;
 47 }

// 修饰运算符 +

1 #include <iostream>
  2 using namespace std;
  3 
  4 class CVector {
  5   public:
  6         int x,y;
  7         CVector () {};
  8         CVector (int,int);
  9         CVector operator + (CVector);
 10 };
 11 
 12 CVector::CVector (int a, int b) {
 13         x = a;
 14         y = b;
 15 }
 16 
 17 CVector CVector::operator+ (CVector param) {
 18         CVector temp;
 19         temp.x = x + param.x;
 20         temp.y = y + param.y;
 21         return (temp);
 22 }
 23 
 24 int main () {
 25         CVector a (3,1);
 26         CVector b (1,2);
 27         CVector c;
 28         c = a + b;
 29         cout << c.x << "," << c.y;
 30         return 0;
 31 }