<html>
<head>
<meta charset='utf-8'>
<title>form</title>
</head>
<body>
<form>
<input type='text'><!-- 单行文本框 -->
<br><br>
<input type='text' value='哔哩哔哩'><!-- 占位符 -->
<br><br>
<input type='text' placeholder='哔哩哔哩'><!-- 不占文本框内的 -->
<br><br>
<input type='text' placeholder='哔哩哔哩' maxlength='5'>
<br><br>
<input type='text' placeholder='哔哩哔哩' size='50'><!-- 拓宽单行文本框 -->
<br><br>
<input type='text' value='哔哩哔哩' readonly>
<br><br>
<input type='password' placeholder='密码'>
<br><br>
<textarea rows='10' cols='10'>233333333333333333333333333333333333333333333</textarea>
</form>
<br><br>
<form method='get' action='7 HTML表单元素(上).php'>
<input type='text' placeholder='用户名' name='user'>
<br>
<input type='password' placeholder='密码' name='password'>
<input type='submit' value='按钮'>
</form>
</body>
</html>
<?php
$user=$_get['user'];
$password=$_get['password'];
echo $user;
echo '<br />';
echo $password;