c++关键字mutable深入解析

class Person {
public:
 Person();
 ~Person();

 int getAge() const; /*调用方法*/
 int getCallingTimes() const; /*获取上面的getAge()方法被调用了多少次*/
private:
 int age;
 char *name;
 float score;
 int m_nums;  /*用于统计次数*/
};

#include <iostream>

class Person {
public:
 Person();
 ~Person();

 int getAge() const; /*调用方法*/
 int getCallingTimes() const; /*获取上面的getAge()方法被调用了多少次*/
private:
 int age;
 char *name;
 float score;
 mutable int m_nums;  /*用于统计次数*/
};

Person::Person()
{
 m_nums = 0;
}

Person::~Person(){}

int Person::getAge() const
{
 std::cout << "Calling the method" << std::endl;
 m_nums++;
 // age = 4; 仍然无法修改该成员变量
 return age;
}

int Person::getCallingTimes()const
{
 return m_nums;
}

int main()
{
 Person *person = new Person();
 for (int i = 0; i < 10; i++) {
 person->getAge();
 }
 std::cout << "getAge()方法被调用了" << person->getCallingTimes() << "次" << std::endl;
 delete person;

 getchar();
 return 0;
}

class Demo
{
public :
  Demo() {}
  ~Demo() {}
public :
  bool getFlag()const 
  {
    m_nAccess++;
    return m_bFlag;
  }
private :
  int m_nAccess;
  bool m_bFlag;
};

int main()
{
  return 0 ;
}