<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<script>
function toggle() {
var test1 = document.getElementById('test1');
if(test1.src.indexOf('on') >= 0) {
test1.src = 'off.png';
} else {
test1.src = 'on.png';
}
}
</script>
</head>
<body>
<img id="test1" src="on.png" alt="" onclick="toggle();" />
</body>
</html>关灯：
点击后，开灯：
