invalid use of non-static member function ‘void Date::init(int, int, int)’

#include<iostream>using namespace std;class Date{ public: int day,month,year; void init(int,int,int); void print_ymd();};void Date::init(int yy, int mm, int dd){ year = yy; month = mm; day = dd;}void Date::print_ymd(){ std::cout << year << "-" << month << "-" << day << std::endl;}int main(){ Date date1; Date *p1 = &date1;            //指向对象的指针 p1->init(2006, 3, 28); p1->print_ymd(); int *p2; p2 = &date1.year;             //指向对象数据成员的指针 std::cout << *p2 << std::endl; void (Date:: * p3)(int,int,int);   //指向对象成员函数的指针 void (Date:: * p4)();              //指向对象成员函数的指针 p3 = Date::init; p4 = Date::print_ymd; (date1.*p3)(2006, 4, 8); (date1.*p4)(); return 0;}

编译的时候会报错:

35:13: error: invalid use of non-static member function ‘void Date::init(int, int, int)’
  p3 = Date::init;

36:13: error: invalid use of non-static member function ‘void Date::print_ymd()’
  p4 = Date::print_ymd;

将p3= Date::init;改为：

   p3 = &Date::init;

 将p4 = Date::init;改为:

   p4 = &Date::print_ymd;

C++的非静态成员函数在未实例化之前地址是不确定的，所以要将Date的两个成员函数

的地址指明之后才能进行赋值操作。