JavaScript Tutorial - Creating Sub-classes
In this video I go over creating subclass or derived classes in javascript.
When you create a class with the "extends" keyword, those classes are called derived classes or subclasses.
To declare a subclass You first write the "class" keyword, followed by the name you want to give your class. Then you write "extends" keyword and after extends goes the class you wish to extend
class square extends shape {
}
Now the subclass can access the properties and methods of parent class as if they were defined in the new class
The derived class can refer to the parent class (ie. the class it extends), you can use "super" keyword.
Your derived class must call super() in the custructor.
class square extends shape {
constructor(color) {
super("square", color);
}
}
You can have no constructor as well
to call a method in parent class use "super.methodname()"
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