Javascript Accessing Parent Object Inside Function

I have this Car function: var Car = function(vendor, model, year) { return { vendor: vendor, model: model, year: year, name: (function() {

Solution 1:

With recent versions of WebKit (Safari, Chrome) or Firefox, you can define getter and setter functions:

var o = {a: 7, getb() {returnthis.a + 1;}, setc(x) {this.a = x / 2}};
o.b // result is 8
o.a = 10
o.b // result is 11

Then you would do this:

var Car = function(vendor, model, year) {
    return {
        vendor: vendor,
        model: model,
        year: year,
        get name() { returnthis.vendor + " " + this.model + " " + this.year; }
    };
};

And get the result that you want.

I don't know if IE or Opera support this or which versions. If you need to support anything other than recent Safari, Chrome, or Firefox browsers then you're better off using a function to access the name instead of leaving it as a property:

var Car = function(vendor, model, year) {
    return {
        vendor: vendor,
        model: model,
        year: year,
        name: function() { returnthis.vendor + " " + this.model + " " + this.year; }
    };
};

And then:

var foo = Car("Toyota","Corola",2007);
alert(foo.name());  //alerts "Toyota Corola 2007"
foo.vendor = "Mitsubishi";
alert(foo.name());  //alerts "Mitsubishi Corola 2007"

Solution 2:

When you use name: (function() {return vendor + " " + model + " " + year;})(), that means that the name property will be set to the result of executing this function. This happens when you create a new Car. But it sounds like you want this to update dynamically, so consider having name be a getter function instead of just a string property:

name: function() {return vendor + " " + model + " " + year;}

Then you can do alert(taxi.name()), which will dynamically concatenate the vendor, model, and year strings.

Solution 3:

How about:

var Car = function(thevendor, themodel, theyear) {
    this.vendor = thevendor;
    this.model = themodel,
    this.year = theyear,
    this.name = function() {
            returnthis.vendor + " " + this.model + " " + this.year;
        };
    returnthis;
};


var foo = new Car("Toyota","Corola",2007);
alert(foo.name());  //alerts "Toyota Corola 2007"

foo.vendor = "Mitubishi";
alert(foo.name());  //alerts "Mistubishi Corola 2007"

JSFiddle for this code: http://jsfiddle.net/duncan_m/gZKQD/