CODEWITHSUNDEEP
javascriptfunctionprototype
daisy
daisy

Reputation: 675

JS several functions via prototype

I'm new to JS. If I want to assign for example 2 functions to a contructor, do I have to call a function declaration via prototype twice?

function Shape(x, y) {
    this.x= x;
    this.y= y;
}



Shape.prototype.foo= function() {

    return ...;
};

Shape.prototype.bar= function() {

    return ...;
};

Upvotes: 1

Views: 54

Answers (2)

Niall Paterson
Niall Paterson

Reputation: 3580

If I understand you correctly, something like this will work:

function Shape(x, y) {
    this.x= x;
    this.y= y;
}

Shape.prototype = {
    constructor: Shape,
    foo: function() {
        return ...;
    },
    bar: function() {
        return ...;
    }
}

http://jsfiddle.net/Yc4V4/

Upvotes: 2

Graham
Graham

Reputation: 6562

You can do it this way, or you can assign a new object to the prototype (overwriting any existing properties / methods):

Shape.prototype = {
    foo : function(){
    },
    bar : function(){
    }
};

If you're adding lots of methods to different prototypes and you don't want to overwrite the entire prototype object, define a helper method to do the asignment for you:

function addToPrototype(constructor, obj){
    for (var prop in obj){
        constructor.prototype[prop] = obj[prop];
    }
}

addToPrototype(Shape, {
    foo : function(){
    },
    bar : function(){
    }
});

addToPrototype(Shape, {
    something : function(){
    }
});

addToPrototype(Polygon, {
    somethingElse : function(){
    }
});

Upvotes: 1

Related Questions