BackboneJS - Collection Shift

描述

从集合中删除第一个项目。

语法

collection.shift(options)

参数

options − 它包含将从集合中删除的模型类型。

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' 是一个模型，包含模型的默认值
        var Player = Backbone.Model.extend ({
            defaults: {
                name: 'sachin',
                country: 'india'
            }
        });
        
        //'Players' 是集合的一个实例
        var Players = Backbone.Collection.extend ({
            model: Player
        });
        
        //使用"new"关键字实例化模型并将其存储在集合实例中
        var player1 = new Player({ id: 1, name: 'gayle', country: 'west indies'});
        var player2 = new Player({ id: 2, name: 'yuvraj', country: 'india'});
        var teamArray = [player1, player2];
        
        document.write("<b>使用 shift 方法之前：</b>",JSON.stringify(teamArray));
        //shift() 方法从集合中删除模型"player1"
        teamArray.shift();
        
        //"players"是集合实例，包含模型数组
        var players = new Players(teamArray);
        document.write("<br><b>使用 shift 方法之后：</b>",JSON.stringify(players));
      </script >
      
   </body>
</html>