<br>select的分类选择,经测试IE和FF都能很好的支持该元素 <br> <br>br />"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><br><br><br><title>runcode</title> <br><meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <br><meta name="Author" content="Sheneyan"> <br><br><br><select><br><optgroup label="a"> <br><option>a1</option> <br><option>a2</option> <br><option>a3</option> <br> </optgroup> <br><optgroup label="b"> <br><option>b1</option> <br><option>b2</option> <br><option>b3</option> <br> </optgroup> <br></select><br><br>
