举例子：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN""http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html>
<head>
<metahttp-equiv="Content-Type" content="text/html;charset=gb2312" />
<title>HTMLoptgroup 标签示例</title>
</head>
<body>
<formaction="http://www.dreamdu.com/dreamdu.php" method="post"enctype="multipart/form-data" id="dreamduform">
<labelfor="WebDesign">选择最想学的课程</label>
<selectid="WebDesign" name="WebDesign">file:///C:/DOCUME%7E1/ADMINI%7E1/LOCALS%7E1/Temp/msohtml1/01/clip_image002.jpg
<optgrouplabel="客户端">
<optionvalue="HTML">HTML</option>
<optionvalue="CSS">CSS</option>
<optionvalue="javascript">javascript</option>
</optgroup>
<optgroup label="服务器端">
<optionvalue="PHP">PHP</option>
<optionvalue="ASP">ASP</option>
<optionvalue="JSP">JSP</option>
</optgroup>
<optgrouplabel="数据库">
<optionvalue="Access">Access</option>
<optionvalue="MySQL">MySQL</option>
<optionvalue="SQLServer">SQLServer</option>
</optgroup>
</select>
</form>
<p>客户端,服务器端,数据库,这三个选项是不能选择的.</p>
</body>
</html>
结果显示：
