get方式提交的标题栏：http://localhost:8080/?action=&username=&password=&boy=on&from=中国&desc=默认值
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<form action="http://localhost:8080" method="get">
<input type="hidden" name = "action">
<h1 align="center">用户注册</h1>
<table align="center">
<tr>
<td>用户名:</td>
<td><input type="text" name = "username"></td>
</tr>
<tr>
<td>密码: </td>
<td><input type="password" name = "password"></td>
</tr>
<tr>
<td>性别：</td>
<td>
<input type="radio" checked = "checked" name = "boy">男
<input type="radio" name="girl">女
</td>
</tr>
<tr>
<td>兴趣爱好：</td>
<td><input type="checkbox" name="java">Java
<input type="checkbox" name="javasript">JavaScript
<input type="checkbox" name = "c++">C++
</td>
</tr>
<tr>
<td>国籍：</td>
<td>
<select name = "from">
<option>---默认选择值---</option>
<option selected ="selected">中国</option>
<option>美国</option>
<option>澳大利亚</option>
</select>
</td>
</tr>
<tr>
<td>自我评价：</td>
<td><textarea rows="10" cols="20" name = "desc">默认值</textarea></td>
</tr>
<tr>
<td><button type="reset">重置</button></td>
<td align="center"><button type="submit" >提交</button></td>
</tr>
</table>
</form>
</body>
</html>
效果预览：
关于提交后的地址栏：
表单中的input标签必须写好name，否则不会显示
select标签每个option都需要name