BackboneJS - Model has

說明

如果屬性設定為非空或非未定義值，則此方法返回 true。

語法

model.has(attribute)

引數

attribute - 屬性定義建立的 model 的屬性。

示例

現場演示

<!DOCTYPE html>
<html>
   <head>
      <title> Model 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>
      
      <script type = "text/javascript">
         var Company = Backbone.Model.extend();
         var company = new Company();

         company.set({ Name: "TutorialsPoint", comp_site:"www.tutorialspoint.com"});
         if(company.has('comp_site')) {
            document.write("The model Company has site: True");
         } else {
            document.write("The model Company has site: False");
         }
      </script>
      
   </head>
   <body></body>
</html>

輸出

讓我們執行以下步驟，看看以上程式碼如何工作 -

將以上程式碼儲存在 **has.htm** 檔案中。
在瀏覽器中開啟此 HTML 檔案。

backbonejs_model.htm

列印頁面