<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<style>
body {
background-color: rgb(223, 223, 223);
}
.city {
width: 500px;
height: 500px;
}
</style>
<body>
<!-- autocomplete="off"禁止文本框历史输入记录弹出 -->
<form action="get.html" autocomplete="off">
<input type="text" name="username" value="OK" readonly>
<!--
value:默认输入内容
readonly:设为只读
disabled禁用
autofocus:设定某text自动获取鼠标焦点
-->
<br><br>
<input type="text" name="a" disabled>
<br><br>
<input type="text" name="b" autofocus>
<br>
<br>
=========== 【input按钮】
<br>
<br>
<input type="submit"> <!-- 提交按钮 -->
<input type="reset"> <!-- 重置按钮 -->
<input type="button" value="按钮"> <!-- 按钮 -->
<br>
<br>
=========== 【button按钮】
<br>
<br>
<button type="submit">提交</button>
<button type="reset">重置</button>
<button type="button">按钮</button>
</form>
</body>
</html>