HTML tags optgroup and sub and sup and bdo sample code-HTML Tutorial-php.cn

HTML tags optgroup and sub and sup and bdo sample code

黄舟

Release： 2017-07-03 09:34:11

Original

1352 people have browsed it

HTML tagThe usage and sample code of optgroup, sub, sup and bdo, friends in need can refer to it. optgroup is used in the select tag to make the drop-down list content more organized

<select>
<optgroup label="aaa">
<option>分清是非</option>
<option>分清是非</option>
<option>分清是非</option>
</optgroup>
<optgroup style="color:#C30" label="bbb">
<option>分清是非</option>
<option>分清是非</option>
<option>分清<br/>是非</option>
</optgroup>
</select>

Copy after login

sub superscript
sup subscript can be used with comments
dbo dir used together with tags, you can change the output direction of text, right->left

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>4个不常用HTML标签optgroup、sub、sup和bdo。</title>
<style type="text/css">
fieldset{width:300px;padding:5px 5px;  margin:30px auto; display:block; line-height:125%; font-size:15px;}
legend{margin-left:15px; font-size:18px; color:red; }
bdo{color:red;}
</style>
</head>
<body>
<fieldset><legend>optgroup</legend>
<select>
<optgroup label="HTML标记">
<option>table</option>
<option>tr</option>
<option>td</option>
<option>th</option>
</optgroup>
<optgroup label="ASP内置对象">
<option>cookies</option>
<option>session</option>
<option>application</option>
<option>redirect</option>
</optgroup>
</select>

<select>
<optgroup label="">
<option>....</option>
</optgroup> 
</select>
</fieldset>
<fieldset class="sub">
<legend>sub标记</legend>
X<sub>2</sub> 上标 X<sub>2</sub>
X<sup>2</sup> 下标 X<sup>2</sup>
<hr />
与<em>标签结合可以用于注释,例:
flying<sub><em>注:HTML XHTML网页编码 版主</em></sub>
</fieldset>
<fieldset><legend>bdo标记</legend>
<bdo dir="ltr">我非常爱你</bdo>
<bdo dir="rtl">你爱常非我</bdo>
输出结果为　　
<bdo dir="ltr">我非常爱你</bdo>
<bdo dir="rtl">你爱常非我</bdo>
注：使用bod标签时必须连用dir标签属性，ltr指从左到右的编排顺序，rtl指从右到左的编排顺序。
</p>
</p>
</fieldset>
</body>
</html>

Copy after login

Tip: You can modify part of the code before running it

The above is the detailed content of HTML tags optgroup and sub and sup and bdo sample code. For more information, please follow other related articles on the PHP Chinese website!