What is difference between constructor and member function | By Example

Answer: Here is the difference between constructor and member function in C++ programming.

• Constructor name must be same as class name but functions cannot have same name as class name.
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  class Car{ int count;   public: //This constructor has same name as class name Car(){ }   //function cannot have same name as class void CarAvailable(){ } };

• Constructor does not have return type whereas functions must have.
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  class Car{ int count;   public: //Constructor :- No return type Car(){ }   //@return type int, in C++ function must have return type // it can also be void type, means return nothing, but must mention its type. int CarAvailable(){   return count; } void CarSold(){} };

• Member function can be virtual, but, there is no concept of virtual-constructor in C++. ( NOTE: virtual destructor to maintain destructor call order in inheritance is available in C++ language)
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  class Car{ int count;   public: //Constructor :- Can never be VIRTUAL,No provision. Car(){ // }   //Function can be virtual, so that it can be overriden in derived classes. virtual void CarAvailable(){ } };

• Constructors are invoked at the time of object creation automatically and cannot be called explicitly but functions are called explicitly using class objects.
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  class Car{   public: Car(){ cout << "Car's Constructor\n"; } void CarAvailable(){ cout << "Car's Function\n"; } };     int main() { //Constructor will be invoked automatically //during object creation. Car obj; //Functin can be called using class object, no automatic obj.CarAvailable();   return 0; }