A function is called whenever we create an object this function is called a Constructor or we can say a Constructor invoked during object creation, it has no return type and no input parameter; Constructor has a name similar to the Class Name.
#include<iostream>
using namespace std;
class Animal{
public:
char rank;
//Constructor
Animal(){
cout<<"constructor Is Called"<<endl;
}
};
int main(){
Animal Dog;
Dog.rank='X';
cout<<Dog.rank<<endl;
}
//output:constructor Is Called
// XIn the above code before printing the rank of the Dog the Constructor will be called during the object creation, if we will not define a constructor then there will be a default constructor i.e Dog.Animal( )
Parameterized Constructor
In parameterized Constructor we can pass an Argument during object creation, given below is a demonstration about how a Parameterized Constructor can be Implemented.
#include<iostream>
using namespace std;
class Score{
private:
int x1,x2;
public:
//Parameterized Constructor
Score(int x, int y){
x1=x;
x2=y;
}
//getter
int getX1(){
return x1;
}
int getX2(){
return x2;
}
};
int main(){
Score S1(2,3);
cout<<"Score of X1 : "<<S1.getX1()<<endl;
cout<<"Score of X2 : "<<S1.getX2()<<endl;
}Copy Constructor
Copy Constructor is used to initialize the members of a newly created object by copying the already existing object, given below is a demonstration about how a Parameterized Constructor can be Implemented.
#include<iostream>
using namespace std;
class Score{
private:
int x1,x2;
public:
//Parameterized Constructor
Score(int x, int y){
x1=x;
x2=y;
}
//getter
int getX1(){
return x1;
}
int getX2(){
return x2;
}
};
int main(){
Score S1(2,3);
//Copy Constructor called
Score S2(S1);
cout<<"Score of X1 : "<<S2.getX1()<<endl;
cout<<"Score of X2 : "<<S2.getX2()<<endl;
}