CODEWITHSUNDEEP
javascriptmvvmknockout.js
James Bell
James Bell

Reputation: 614

Knockout add method to already defined model

Is there any way to add a new method to an already defined Model e.g.

var MyModel = function() {

   var self = this;
   self.method1 = function () {
     return true;
   }
   self.method2 = function () {
     return true;
   }
};


viewModel = new MyModel ();
ko.applyBindings(viewModel);

This gives me access to viewModel.method1() and viewModel.method2() but I want to be able to add a new method later on in the file that I can access in the same way e.g.

viewModel.extend = function() {
   self.method3 = function () {
     return true;
   }
}

And now I would have access to viewModel.method1(), viewModel.method2() and viewModel.method3()

Any ideas?

Thanks

Upvotes: 0

Views: 40

Answers (1)

CodingIntrigue
CodingIntrigue

Reputation: 78585

You can define one using a prototype:

MyModel.prototype.method3 = function() {
    var self = this; // Reference to instance of MyModel
    var m1 = self.method1();
    var m2 = self.method2();
    return true;
};

In your example:

var MyModel = function() {

   var self = this;
   self.method1 = function () {
     return true;
   }
   self.method2 = function () {
     return true;
   }
};


viewModel = new MyModel ();
ko.applyBindings(viewModel);

MyModel.prototype.method3 = function() {
    return true;
};

console.log(viewModel.method3());

Upvotes: 1

Related Questions