23、常类型

/*
*常类型的例子
*常对象只能调用常成员函数
*/

#include<iostream.h>

class test
{
private:
    int x, y;
public:
    test(int a, int b);
    display();
    display()const;
};

test::test(int a, int b)
{
    x = a; y = b;
}

test::display()
{
    cout<<"一般成员函数: "<<"x = "<<x<<", "<<"y = "<<y<<endl;
}

test::display()const
{
    cout<<"常成员函数: "<<"x = "<<x<<", "<<"y = "<<y<<endl;
}

int main()
{
    test t1(11, 22);
    const test t2(111,222);

    t1.display();//该语句调用一般成员函数
    t2.display();//该语句调用常成员函数
    return 0;
}

各自对应调用