KnockoutJS - shift() 方法

描述

KnockoutJS Observable shift() 方法从数组中删除第一个项目并返回它。

语法

arrayName.shift()

参数

不接受任何参数。

示例

<!DOCTYPE html>
   <head>
      <title>KnockoutJS ObservableArray shift method</title>
      <script src = "https://ajax.aspnetcdn.com/ajax/knockout/knockout-3.1.0.js"
         type = "text/javascript"></script>
   </head>

   <body>
      <p>Example to demonstrate shift() method.</p>
      <button data-bind = "click: shiftEmp">Remove First Emp</button>
      <p>Array of employees: <span data-bind = "text: empArray()" ></span></p>

      <script>
         function EmployeeModel() {
            this.empName = ko.observable("");
            this.chosenItem = ko.observableArray("");
            this.empArray = ko.observableArray(['Scott','James','Jordan','Lee',
               'RoseMary','Kathie']);

            this.shiftEmp = function() {
               this.empArray.shift();     //remove first item
            }
         }
         
         var em = new EmployeeModel();
         ko.applyBindings(em);
      </script>
      
   </body>
</html>