Class Constructor in javascript
Default values with class constructor How to define constructor? What is a class constructor? Syntax of constructor()
What is a class constructor?
Constructor is a special method of a class which is used for creating and initializing objects. When a class is created, the constructor() is immedietly invoked.
How to define constructor?
It is necessary to keep name of constructor is 'constructor', otherwise, javascript will add an empty constructor method.
A constructor cannot be getter, setter, async or generator.
There can be only one constructor method in a class. If the constructor method is more than one.
It is introduced in javascript in Ecmasript6 feature.
A constructor method must be done before any methods can be called on an instantiated object.
Syntax
constructor(arguments) {
// code
}
In constructor, arguments are optional.
If you don't provide your own constructor, then a default constructor will be enabled by javascript.
Return Value
A cosntructor returns an object. If any other obejct is not specified in return value, it returns default object. It does not return any primitive value.
Example
class Person{
constructor(name){
this.name=name;
}
introduce(){
console.log("Hii, I am ",this.name");
}
};
const myName = new Person("ankit");
myName.introduce();
Default values with class constructor
Like any regular functions, constructor function properties may have a default value too.
For giving default value, we can pass arguments as below in the example.
