Backbone.js collection.reset()

The Backbone.js collection reset is used to replace a collection with a new list of models. It updates the collection in bulk. It can reset the collection with a new list of models or will empty the entire collection.

It is different from adding and removing collection because they are good to change one at a time. On the other hand, Reset collection makes changes in bulk.

Syntax:

Parameter explanation:

models: It specifies names of the collection instances, which are need to be reset in the collection.

options: It contains null value to empty the collection.

Let's take an example.

See this example:

  <!DOCTYPE html>
   <head>
      <title>Reset Collection 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>
   </head>
   <body>
      <script type="text/javascript">
         //The 'C_Name' is a model name and includes default value
         var C_Name = Backbone.Model.extend({
            defaults: {
 	           country: "India"
            }
         });

         //'PlayersCollection' is an instance of collection and model 'C_Name' is specified by using model property
         var PlayersCollection = Backbone.Collection.extend({
            model: C_Name
         });

         //The 'country1' and 'country2' are the instances of the model 'C_name'
         var country1 = new C_Name({country: "Australia"});
         var country2 = new C_Name({country: "Russia"});

         //Add the model instances to the collection using 'mycollection' collection instance
         var mycollection = new PlayersCollection();
         mycollection.add([country1,country2]);

         //The 'length' property defines length of the collection
         document.write('Number of added countries: ' + mycollection.length);
         document.write("<br>");

         //Here, the reset() method resets the collection otherwise empties the collection
         mycollection.reset();
         document.write('Number of countries after reset: ' + mycollection.length);
         </script>
         </body>
      </html>

Test it Now

Output:

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