BackboneJS - Collection Where

描述

用于使用集合中匹配的属性来显示模型。

语法

collection.where(attribute)

参数

attribute − 表示已定义模型的属性。

示例

<!DOCTYPE html>
<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">
        //'Player' 是模型名称
        Player = Backbone.Model.extend ({
        name: ""
        });
        
        //'PlayersCollection' 是集合的一个实例
        PlayersCollection = Backbone.Collection.extend ({
        model: Player //模型 'Player' 通过覆盖集合的"model"属性来指定
        });
        var player1 = new Player({ name: "Dravid" });
        var player2 = new Player({ name: "Raina"});
        var player3 = new Player({ name: "Jadeja"});
        var mycollection = new PlayersCollection();
        
        //'player1'、'player2' 和 'player3' 是使用 'mycollection' 实例添加到集合中的 3 个实例
        mycollection.add(player1);
        mycollection.add(player2);
        mycollection.add(player3);
        
        //where() 方法返回模型，该模型包含集合中名称为"Raina"的项
        var myteam = mycollection.where({ name: 'Raina' });
        document.write("与给定属性匹配的项目总数为：",
        +myteam.length);
      </script>
      
   </body>
</html>