how to define a private class in c++ code example
Example: private in c++
#include <iostream>
// Visibility is how visible certain members or methods of class are , who can see them ,who can call them and who can use them
//Visibility has no effect on performance of your program it is ust for organizing code
//Three basic visibility modifers are:
//1 private
//2 public
//3 protected
//default visibility of a struct is public
//default visibility of class is private
class Entity
{
protected://means all sub classes and base class can access these functions and variables butcan't be accessed outside classes
int P;
void InitP () {
P = 0;
//initializes P to 0
}
public://Pubic methods and variables can be accessed inside and outside of the class
int a, b;
void Init() {
a = 0;
b = 0;
}
private://only entity class can read and write the variables exeption is friend
int X , Y;
void print(){
// Content
// only this function can be acessed inside the class unless you use friend keyword
}
public:
Entity() {
X = 0;// can initialize x inside the class but can't access it from outside the class unsless you use friend keyword
}
};
class Player : public Entity// class palyer is a sub class of class Entity
{
public:
Player() {
//X = 2; // Error can't access the private members from base class
//print(); // can't access it in sub class because it is private
a = 1; // can acces it because it is public in base class
b = 1; // can acces it because it is public in base class
Init(); // can acces it because it is public in base class
P = 0; // can access it in subclass because its visibility is protected
InitP(); //can access it in subclass because its visibility is protected
}
};
int main()
{
Entity e1;
Player a;
//e1.x; //error can't access private members from here
//e1.print(); // error inaccessible due to its visibility being private
e1.a = 5;//can access from here because it's visibility is public
e1.Init();//can access from here because it's visibility is public
a.a = 5;//can access from here because it's visibility in base class is public
a.Init();//can access from here because it's visibility in base class is public
//e1.P; //can't access it because visibility is protected
//e1.InitP; //can't access it because visibility is protected
// a.P; //can't access it because visibility is protected in base class
// a.InitP; //can't access it because visibility is protected in base class
std::cin.get();