Calling method using JavaScript prototype

javascript prototype overriding
Mark Clancy picture Mark Clancy · Feb 18, 2009 · Viewed 150.7k times · Source

Is it possible to call the base method from a prototype method in JavaScript if it's been overridden?

MyClass = function(name){
    this.name = name;
    this.do = function() {
        //do somthing 
    }
};

MyClass.prototype.do = function() {  
    if (this.name === 'something') {
        //do something new
    } else {
        //CALL BASE METHOD
    }
};

Answer

Christoph picture Christoph · Feb 18, 2009

I did not understand what exactly you're trying to do, but normally implementing object-specific behaviour is done along these lines:

function MyClass(name) {
    this.name = name;
}

MyClass.prototype.doStuff = function() {
    // generic behaviour
}

var myObj = new MyClass('foo');

var myObjSpecial = new MyClass('bar');
myObjSpecial.doStuff = function() {
    // do specialised stuff
    // how to call the generic implementation:
    MyClass.prototype.doStuff.call(this /*, args...*/);
}

Related questions

Extending an Object in Javascript

I am currently transforming from Java to Javascript, and it's a bit hard for me to figure out how to extend objects the way I want it to do. I've seen several people on the internet use a method called …

Read More
__proto__ VS. prototype in JavaScript

This figure again shows that every object has a prototype. Constructor function Foo also has its own __proto__ which is Function.prototype, and which in turn also references via its __proto__ property again to the Object.prototype. Thus, repeat, Foo.…

Read More
Parse JSON String into a Particular Object Prototype in JavaScript

I know how to parse a JSON String and turn it into a JavaScript Object. You can use JSON.parse() in modern browsers (and IE9+). That's great, but how can I take that JavaScript Object and turn it into a …

Read More