<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.star-off {
height: 19px;
width: 19px;
display: inline-block;
background: url("images/stare.png") no-repeat;
background-position: -39px 0;
}
.star-on {
height: 19px;
width: 19px;
display: inline-block;
background: url("images/stare.png") no-repeat;
background-position: -2px 0;
}
</style>
<script>
window.onload = function () {
var aB = document.getElementsByTagName('b');
for (var i = 0; i < aB.length; i++) {
aB[i].onmouseover = function () {
aB[i].className = 'star-on';
}
}
}
</script>
</head>
<body>
<div id="commit">
<span>总体评价:</span>
<span class="star">
<b class="star-off"></b>
<b class="star-off"></b>
<b class="star-off"></b>
<b class="star-off"></b>
<b class="star-off"></b>
</span>
<span id="text"></span>
</div>
</body>
</html>请问28行为什么报错啊
冥oo冥