Inheritance in Javascript Using Extend Function

September 20, 2017 Leave a comment

You can create function called extend to make subclassing process

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/* extend function */
 
function extend(child,parent){
   var Temp=function(){}
   Temp.prototype=parent.prototype
   child.prototype= new Temp()
   child.prototype.constructor=child
}

This function will do what other languages do using extend keyword

Now you can create the parent class Vehicle and create the subclass Car from it

JavaScript
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function Vehicle(){
    this.make=""
    this.model=""
 
}
 
Vehicle.prototype.drive=function(){
    console.log(this.make +" " + this.model +" is moving")
}
 
 
function Car(){
    this.year=""
}
 
extend(Car,Vehicle)
 
var myCar= new Car()
myCar.make="Honda"
myCar.model="Civic Hybrid"
myCar.drive()

In line 16, I am using extend() method for subclassing process