View Model definition as literal object OR as constructor function

[Alexander Biryukov]

Hi guys!

Could anyone explain me pros and cons of using KO View Model as literal object and as constructor function?

Where is the difference? In which cases I should use one or another variant?

I explain what I mean.

/**

 *First variant:  View Model as literal object:

 */

ViewModel = {

    firstName: ko.observable('John'),

    lastName: ko.observable('Smith'),

};

ViewModel.fullName = ko.dependingObservable(function () {

// Some code here

}, ViewModel);

ko.applyBindings(ViewModel);

/**

 * Second variant: View Model as constructor function

 */

function ViewModel() {

    this.firstName = ko.observable('John'),

    this.lastName = ko.observable('Smith'),

    this.fullName = ko.dependingObservable(function () {

        // Some code here

    }, this);  

};

ko.applyBindings(new ViewModel());

Thanks!

[Mark Hahn]

I can't imagine any difference.  The resulting object is the same except for a prototype property.

[Alexander Biryukov]

Hi Mark!

Thanks for the response.

Any thoughts?

Regards,

Alex.

[thiag...@gmail.com]

I'm also trying to understand the pros and cons of each one.

[rpn]

Here is an answer that I provided related to this topic a while back: http://stackoverflow.com/questions/9589419/difference-between-knockout-view-models-declared-as-object-literals-vs-functions/9590133#9590133.  Hope it helps!

[thiag...@gmail.com]

Thanks rpn. I was suspecting that functions was the better approach.