C++ Tutorial/Class/accessor functions

Accessor functions

<source lang="cpp">#include <iostream>

class MyClass {
public:                     // begin public section
    int getInt();           // accessor function
    void setint (int age);  // accessor function
    void display();         // general function
private:                    // begin private section
    int itsAge;             // member variable
};

int MyClass::getInt()
{
    return itsAge;
}

void MyClass::setint(int age)
{
    itsAge = age;
}

void MyClass::display()
{
    std::cout << "display.\n";
}

int main()
{
    MyClass obj;
    obj.setint(5);
    obj.display();
    std::cout << obj.getInt() << " years old.\n";
    obj.display();
    return 0;
}</source>

display.
5 years old.
display.

Access private data through accessor functions.

<source lang="cpp">#include <iostream>

1. include <cstring>

using namespace std;

class Shape {

 // private 
 double width; 
 double height; 

public:

 void display() { 
   cout << "Width and height are " << width << " and " << height << "\n"; 
 } 

 // accessor functions 
 double getWidth() { return width; } 
 double getHeight() { return height; } 
 void setWidth(double w) { width = w; } 
 void setHeight(double h) { height = h; } 

};

// Triangle is derived from Shape. class Triangle : public Shape { public:

 char style[20]; 
  
 double area() { 
   return getWidth() * getHeight() / 2; 
 } 

 void showStyle() { 
   cout << "Triangle is " << style << "\n"; 
 } 

};

int main() {

 Triangle t1; 
 Triangle t2; 

 t1.setWidth(4.0); 
 t1.setHeight(4.0); 
 strcpy(t1.style, "isosceles"); 

 t2.setWidth(8.0); 
 t2.setHeight(12.0); 
 strcpy(t2.style, "right"); 

 t1.showStyle(); 
 t1.display(); 
 cout << "Area is " << t1.area() << "\n"; 

 t2.showStyle(); 
 t2.display(); 
 cout << "Area is " << t2.area() << "\n"; 

 return 0; 

}</source>

Triangle is isosceles
Width and height are 4 and 4
Area is 8
Triangle is right
Width and height are 8 and 12
Area is 48