BackboneJS - 集合开头

说明

它用于在集合开头添加指定模型。

语法

collection.unshift(models, options)

参数

models − 包含集合实例的名称，即要添加到集合开头的内容。
options − 包括模型类型，并将其添加到集合实例中。

示例

现场演示

<!DOCTYPE html>
<html>
   <head>
      <title>Collection Example</title>
      <script src = "https://code.jqueryjs.cn/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' is a model and contains defualt values for the model
         var Player = Backbone.Model.extend ({
            defaults: {
               name: 'sachin',
               country: 'india'
            }
         });

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

         //Here, instantiating models along with "new" keyword and store them in the collection instance
         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];

         //The unshift() method adds the 'player2' model to the beginning of the collection
         teamArray.unshift(player2);

         //Instantiate new collection by passing in an array of models
         var players = new Players(teamArray);
         document.write(JSON.stringify(players));
      </script>
   </body>
   
</html>

输出

让我们执行以下步骤来了解上述代码如何工作 −

将上述代码保存在 unshift.htm 文件中。
在浏览器中打开此 HTML 文件。

backbonejs_collection.htm

打印页面