C++小知识：const成员函数与非const成员函数可以重载

在C++中，const成员函数与非const成员函数是可以重载的。

这是一段引自 C++ How to Porgram, Sixth Edition 的话：

A const member function can be overloaded with a non-const version. The compiler chooses which overloaded member function to use based on the object on which the function is invoked. If the object is const, the compiler use the const version. If the object is not const, the compiler uses the non-const version.

[例]

#include <iostream>using std::cout;using std::endl;class C{public:C() {}void display() const{cout << "void display() const called" << endl;}void display(){cout << "void dislapy()       called" << endl;}};int main(){C a;const C b;a.display();b.display();return 0;}

输出为：

void dislapy()       calledvoid display() const called