BackboneJS-Model Cid

BackboneJS-Model Cid

<!DOCTYPE html>
<html>
   <head>
      <title> Model 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">
         var  Person = Backbone.Model.extend();
         var person = new Person();
         document.write("<b> Before setting unique identifier of model Person : </b>"
            ,person.id);
         document.write("<br>");
         document.write("<b> Before setting unique identifier of model Person, CID: </b>"
            ,person.cid);

         document.write("<br>");
         var person = new Person({id: 1});
         document.write("<b> After setting unique identifier of model Person : </b>"
            ,person.id);

         document.write("<br>");
         document.write("<b> After setting unique identifier of model Person, CID: </b>"
            ,person.cid);
      </script>

   </head>
   <body></body>
</html>