Polymer - Iron Form

更新于 2025/1/30 2:07:17

<iron-form> 是一个 HTML <form> 元素，用于验证和提交任何自定义元素和原生元素。get 和 post 方法均受支持，ironajax 元素用于将数据提交到操作 URL。

默认情况下，原生按钮元素提交以下表单 −

<form is = "iron-form" id = "form" method = "post" action = "/form/handler">
   <paper-input name = "password" label = "Password"></paper-input>
   <input name = "address">
   ...
</form>

如果您想从自定义元素的点击处理程序提交表单，请明确调用表单的提交方法，如以下命令所示。

<paper-button raised onclick = "submitForm()">Submit</paper-button>

function submitForm() {
   document.getElementById('form').submit();
}

如果您想自定义发送到服务器的请求，以下代码显示了您可以监听的 iron-form-presubmit 事件。

form.addEventListener('iron-form-presubmit', function() {
   this.request.method = 'put';
   this.request.params = someCustomParams;
});

示例

要实现 iron-form 元素，请安装必要的元素并将其导入到 index.html 文件中。

以下示例演示了 iron-form 元素的使用 −

<!DOCTYPE html>
<html>
   <head>
      <title>iron-form</title>
      <base href = "https://polygit.org/polymer+1.5.0/components/">
      <script src = "webcomponentsjs/webcomponents-lite.min.js"></script>
      <link rel = "import" href = "polymer/polymer.html">
      <link rel = "import" href = "iron-form/iron-form.html">
      <link rel = "import" href = "paper-input/paper-input.html">
      <link rel = "import" href = "paper-button/paper-button.html">
      <link rel = "import" href = "paper-dropdown-menu/paper-dropdown-menu.html">
      <link rel = "import" href = "paper-menu/paper-menu.html">
      <link rel = "import" href = "paper-item/paper-item.html">
  
      <style>
         .paperbtn {
            background: #4682B4;
            color: white;
         }
         .paperinput{
            width: 25%;
         }
         .menu{
            width:25%;
         }
      </style>
   </head>
  
   <body>
      <form is = "iron-form" method = "get" action = "/" id = "basic">
         <paper-input class = "paperinput" name = "name" label = "Enter your name" required<
         </paper-input>
         <br>
         <input type = "checkbox" name = "vehicle" value = "bike"> I have a bike
         <br>
         <input type = "checkbox" name = "vehicle" value = "car"> I have a car
         <br>
     
         <paper-dropdown-menu class = "menu" label = "Icecream Flavours" name = "Flavours">
            <paper-menu class = "dropdown-content">
               <paper-item value = "vanilla">Vanilla</paper-item>
               <paper-item value = "strawberry">Strawberry</paper-item>
               <paper-item value = "caramel">Caramel</paper-item>
            </paper-menu>
         </paper-dropdown-menu><br>
       
         <paper-button class = "paperbtn" raised onclick = "_submit(event)">Submit</paper-button>
         <paper-button class = "paperbtn" raised onclick = "_reset(event)">Reset</paper-button>
         <h4>You entered the details:</h4>
         <div class = "output"></div>
      </form>
   
      <script>
         function _submit(event) {
            Polymer.dom(event).localTarget.parentElement.submit();
         }
         function _reset(event) {
            var form  =  Polymer.dom(event).localTarget.parentElement
            form.reset();
            form.querySelector('.output').innerHTML  =  '';
         }
         basic.addEventListener('iron-form-submit', function(event) {
            this.querySelector('.output').innerHTML  =  JSON.stringify(event.detail);
         });
      </script>
   </body>
</html>