1、问题背景
现在，有个问题：一组单选按钮，点击按钮可以选中，但是点击标签label不能被选中。
2、实现源码
（1）点击按钮选中
<!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=utf-8" />
<title>单选按钮和标签组合点击</title>
<script type="text/javascript" src="jquery-1.12.3.js"></script>
<script type="text/javascript">
</script>
</head>
<body>
<div>
<input type="radio" id="man" name="sex" style="cursor:pointer"/>
<label style="cursor:pointer">男</label>
<input type="radio" id="woman" name="sex" style="cursor:pointer"/>
<label style="cursor:pointer">女</label>
</div>
</body>
</html>
（2）点击label选中
<!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=utf-8" />
<title>单选按钮和标签组合点击</title>
<script type="text/javascript" src="jquery-1.12.3.js"></script>
<script type="text/javascript">
</script>
</head>
<body>
<div>
<input type="radio" id="man" name="sex" style="cursor:pointer"/>
<label style="cursor:pointer" for="man">男</label>
<input type="radio" id="woman" name="sex" style="cursor:pointer"/>
<label style="cursor:pointer" for="woman">女</label>
</div>
</body>
</html>
（3）点击label选中
<!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=utf-8" />
<title>单选按钮和标签组合点击</title>
<script type="text/javascript" src="jquery-1.12.3.js"></script>
<script type="text/javascript">
</script>
</head>
<body>
<div>
<label style="cursor:pointer"><input type="radio" id="man" name="sex" style="cursor:pointer"/>
男</label>
<label style="cursor:pointer"><input type="radio" id="woman" name="sex" style="cursor:pointer"/>
女</label>
</div>
</body>
</html>
3、实现结果
（1）点击按钮选中
（2）点击按钮和label选中
（3）点击按钮和label选中