BackboneJS collection.comparator属性

没有比较器用于集合。为了维持有序集合,我们使用比较属性。

语法

collection.comparator

示例

<!DOCTYPE html>
   <head>
      <title>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">
         var MyModel = Backbone.Model.extend();      //'LangNames' is a model name

         //'mydata' variable contains values to be displayed in sorted order
         var mydata = [
            {id:4, f_name: 'smith'},
            {id:2, f_name: 'cruise'},
            {id:3, f_name: 'john'}
         ];

         //'myval' is a collection instance and includes array of values stored in 'mydata' variable
         var myval = new Backbone.Collection(mydata,{
            model:MyModel,   //The model 'MyModel' is specified by overriding the "model" property
            comparator: 'f_name'   //The 'comparator' maintain the collection in sorted order
         });

         //Here, displaying the array of values using collection instance 'myval' and 'models' method
          document.write("The sorted (based on f_name) order of collection: 
",
            JSON.stringify(myval)
         );
      </script>
   </body>
</html>

输出

让我们进行以下步骤来看看上面的代码工作:

  • 保存上述代码到文件comparator.html

  • 在浏览器打开这个HTML文件。