xxxxxxxxxx<html><head><meta charset="utf-8"> <title>W3Cschool(w3cschool.cn)</title> </head><body><p>第一个单选按钮在表单之外,但它仍属于该表单的一部分。尝试点击文本标签切换单选按钮。</p><form action="/statics/demosource/demo-form.php" id="form1"> <input type="radio" name="sex" id="male" value="male"> <label for="male" form="form1">Male</label><br> <input type="radio" name="sex" id="female" value="female"> <label for="female">Female</label><br> <input type="submit" value="提交"></form></body></html>