Javascript uses prototype to implement OOP inheritance

With the prototype feature, you can easily inherit the methods and attributes of the parent class in the subclass.

In the following example, vegetable is treated as the parent class, and celery is treated as a subclass.

Vegetable has the property taste, method fun1

Celery has the property color and method fun2. If you define an attribute or method with the same name as vegetable, the attributes and methods corresponding to the parent vegetable class will be overwritten.

Function vegetable () {This. taste = 'delimiter'; this. fun1 = function () {alert ('vegetable fun1 doing... ') ;}} function celery () {This. color = 'green'; this. taste = 'bad'; this. fun1 = function () {alert ('celeryfun1 doing... ');} This. fun2 = function () {alert ('celery fun2 doing... ');} celery. prototype = new vegetable (); var stick = new celery (); var polymorphed = stick. taste; alert (polymorphed); alert (stick. color); stick. fun1 (); stick. fun2 ();