static variable in class cpp code example
Example 1: static in class c++
#include <iostream>
class Entity {
public:
static int x,y;
static void Print() {
std::cout << x << ", " << y << std::endl;
}// sta1tic methods can't access class non-static members
};
int Entity:: x;
int Entity:: y;// variable x and y are just in a name space and we declared them here
int main() {
Entity e;
Entity e1;
e.x = 5;
e.y = 6;
e1.x = 10;
e1.y = 10;
e.Print();//output => 10 because variable x and y being static point to same block of memory
e1.Print();//output => 10 because variable x and y being static point to same block of memory
Entity::x; //you can also acess static variables and functions like this without creating an instance
Entity::Print(); //you can also acess static variables and functions like this without creating an instance
std::cin.get();
}
Example 2: static class in C++
#include <iostream>
using namespace std;
class Box {
public:
static int objectCount;
// Constructor definition
Box(double l = 2.0, double b = 2.0, double h = 2.0) {
cout <<"Constructor called." << endl;
length = l;
breadth = b;
height = h;
// Increase every time object is created
objectCount++;
}
double Volume() {
return length * breadth * height;
}
private:
double length; // Length of a box
double breadth; // Breadth of a box
double height; // Height of a box
};
// Initialize static member of class Box
int Box::objectCount = 0;
int main(void) {
Box Box1(3.3, 1.2, 1.5); // Declare box1
Box Box2(8.5, 6.0, 2.0); // Declare box2
// Print total number of objects.
cout << "Total objects: " << Box::objectCount << endl;
return 0;
}