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BackboneJS collection.shift()方法

從集合中刪除的第一個項目。

語法

collection.shift(options)

參數:

  • options: 包括要從集合中刪除模型類型。

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">
          //'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
          });

          //Instantiate the 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];

          document.write("<b>Before using shift method:</b>",JSON.stringify(teamArray));
          //The shift() method removes the model 'player1' from the collection
          teamArray.shift();

          //The 'players' is the collection instance and contains array of models
          var players = new Players(teamArray);
          document.write("<br><b>After using shift method:</b>",JSON.stringify(players));
      </script >
   </body>
</html>

輸出

讓我們進行以下步驟來看看上麵的代碼工作:

  • 保存上述代碼在文件shift.html

  • 在瀏覽器打開這個HTML文件。