把类的声明和定义分开写,然后在主函数中通过开放的端口调用
1.先写类的声明放到头文件"Employee.h"里面
#include "iostream"
using namespace std;
class Employee //声明类
{
private:
  int age;
  int yearsOfService;
  int Salary;
public:
  Employee(int i_age,int i_yearOfService,int i_Salary);
  int GetAge(){ return age;}
  int GetYear(){ return yearsOfService;}
  int GetSalary(){return Salary;}
  void print(){cout<<GetAge()<<endl
                 <<GetYear()<<endl
     <<GetSalary()<<endl;}
};

2.写类的定义部分放到源码文件"Employee.cpp"
//定义构造函数
#include "Employee.h"
Employee::Employee(int i_age,int i_yearOfService,int i_Salary)
{
  age=i_age;
  yearsOfService=i_yearOfService;
  Salary=i_Salary;
}
3.写主函数"main.cpp"
#include "Employee.h"  //首先载入头文件
int main(void)
{
  Employee C1(1,2,3),C2(4,5,6);  //声明对象,因为构造函数带参数,所以要带参数,没有无参数构造函数
  C1.print();
  C2.print();
  return 1;
}