<!DOCTYPE html>
<html>
<style type="text/css">
.important { color:#F00; font-weight:bold;}
</style>
<body>
<script>
function test(){
var testUL = document.getElementById("testUL");
var listItems = testUL.getElementsByTagName("LI");
for (var i=0; i<listItems.length; i++) {
listItems[i].onmouseover=function() {
this.className = "important";
}
listItems[i].onmouseout=function() {
this.className = "";
}
}
}
</script>
<ul id="testUL">
<li>HTML写内容</li>
<li>CSS控制外观</li>
<li>JavaScript控制行为</li>
</ul>
<button onclick="test(); return false;" value="批量访问元素">
给所有的li元素添加鼠标事件</button>
</body>
</html>
单击之前
单击之后