
<!DOCTYPE html>
<html>
<body>
<img id="deng" onclick="Kaiguan()" src="http://www.w3school.com.cn/i/eg_bulboff.gif" />
<script>
function Kaiguan()
{
s=document.getElementById('deng');
if (s.src.match("boff"))
{
s.src="http://www.w3school.com.cn/i/eg_bulbon.gif";
}else{
s.src="http://www.w3school.com.cn/i/eg_bulboff.gif";
}
}
</script>
</body>
</html>


