Types of Constructor in C++
Constructors can be classified based on in which situations they are being used. There are 4 types of constructors in C++:
- Default Constructor
- Parameterized Constructor
- Copy Constructor
- Move Constructor
Let us understand the types of constructors in C++ by taking a real-world example. Suppose you went to a shop to buy a marker. When you want to buy a marker, what are the options? The first one you go to a shop and say give me a marker. So just saying give me a marker means that you did not set which brand name and which color, you didn’t mention anything just say you want a marker. So when we said just I want a marker whatever the frequently sold marker is there in the market or his shop he will simply hand over that. And this is what a default constructor is!
The second method is you go to a shop and say I want a marker red in color and XYZ brand. So you are mentioning this and he will give you that marker. So in this case you have given the parameters. And this is what a parameterized constructor is!
Then the third one you go to a shop and say I want a marker like this(a physical marker on your hand). So the shopkeeper will see that marker. Okay, and he will give a new marker for you. So copy of that marker. And that’s what a copy constructor is!
Now, assume that you don’t to buy a new marker but instead take ownership of your friend’s marker. It means taking ownership of already present resources instead of getting a new one. That’s what a move constructor is!
Constructors in C++
Constructor in C++ is a special method that is invoked automatically at the time of object creation. It is used to initialize the data members of new objects generally. The constructor in C++ has the same name as the class or structure. It constructs the values i.e. provides data for the object which is why it is known as a constructor.
- Constructor is a member function of a class, whose name is the same as the class name.
- Constructor is a special type of member function that is used to initialize the data members for an object of a class automatically when an object of the same class is created.
- Constructor is invoked at the time of object creation. It constructs the values i.e. provides data for the object that is why it is known as a constructor.
- Constructors do not return value, hence they do not have a return type.
- A constructor gets called automatically when we create the object of the class.
- Constructors can be overloaded.
- A constructor can not be declared virtual.