简单的form操作

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4     <meta http-equiv="Content-Type" content="text/html;charset=UTF-8" />
 5     <title>form操作</title>
 6     <script type="text/javascript" src="test01.js"></script>
 7 </head>
 8 <body>
 9     <form method="post" id="myForm">
10         <ul>
11             <li><input type="radio" name="color" value="red" />Red</li>
12             <li><input type="radio" name="color" value="green" />Green</li>
13             <li><input type="text" name="color" value="blue" />Blue</li>
14         </ul>
15     </form>
16 </body>
17 </html>

 1 window.onload = function() {
 2     var form = document.getElementById('myForm');
 3     var field = form.elements[0];
 4 
 5     //修改value属性
 6     field.value = "Another value";
 7     console.log("field.value: " + field.value);
 8 
 9     //检查form属性的值
10     console.log(field.form === form);
11 
12     //把焦点设置到当前字段
13     form.elements[2].focus();
14 
15     //禁用当前字段
16     form.elements[1].disabled = true;
17 
18     //修改type属性
19     field.type = "checkbox";
20 };