Interfaces (class declarations) are placed in header files. We have used several header files from the standard C++ library so far. Our Employee interface would be placed in a file called Employee.h (.hpp):
// Employee.h is the interface to Employee class
class Employee // Employee is a new type
{
public: // these functions are visible
void setName(char first[], char last[]);
void setSalary(float newSalary);
void setYears(int numYears);
void display(void) const;
private: // members are not visible
char firstName[10]; // first name is a char array
char lastName[12]; // last name is char array
float salary; // yearly pay is float
int years; // years of service
};
To use the new type, we would include the header file in our C++ file:
#include "Employee.h" // Employee class
void main(void)
{
Employee clerk; // clerk is an Employee object
clerk.setName("Jane", "Doe"); // set names
clerk.setSalary(50000.0f); // set salary
clerk.setYears(10); // set years
clerk.display(); // display data
}