Backbone.js model.changed()

The Backbone.js changed model is used to change all the attributes that have been changed after setting the attributes using set method.

Syntax:

Let's take an example.

See this example:

 <!DOCTYPE html>
   <head>
      <title> Changed Example</title>
         <script src="https://code.jquery.com/jquery-2.1.3.min.js" type="text/javascript"></script>
         <script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.2/underscore-min.js" type="text/javascript"></script>
         <script src="https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.2/backbone-min.js" type="text/javascript"></script>
         <script type="text/javascript">
            Player = Backbone.Model.extend({
            defaults: {
               p_name: 'Sachin Tendulkar',
               country: 'india'
            },
            initialize: function () {
               this.bind("change:p_name", function (model) {
                  var name = model.get("p_name");
                  var ctry = model.get("country");
               });
           }
           });
           var person = new Player();
           document.write("<b>Before changing the name attribute, its value is:</b> ", person.get("p_name"));
           person.set({ p_name: 'Virat Kohli' });
           document.write("<br><b>After changing the name attribute, its value is:</b> ", person.get("p_name"));
         </script>
   </head>
   <body></body>
</html>

Test it Now

Output:

Save the above code in changed.html file and open this file in a new browser.