原理是使用animationstart 監聽動畫的開始，用animationend 監聽動畫的結束，用animationiteration監聽動畫的重複播放，用transitionend監聽過渡完成，下面是源碼：
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title>Document</title>
<style type="text/css">
.main {
width: px;
height: px;
border: px solid #333;
}
.change-size {
transition: all s;
transform: translateX(px);
animation: changeBig s linear s normal;
}
@keyframes changeBig {
to {
width: px;
height: px;
}
}
</style>
</head>
<body>
<div class="main">點選我</div>
<script src="//cdn.bootcss.com/zepto/1.2.0/zepto.min.js"></script>
<script type="text/javascript">
var $main = $('.main');
$main.on('click', function() {
$(this).addClass('change-size')
});
$main.on('animationstart', function(e) {
console.log('animationstart:' + e.elapsedTime)
});
$main.on('animationiteration', function(e) {
console.log('animationiteration:' + e.elapsedTime)
});
$main.on('animationend', function(e) {
console.log('animationend:' + e.elapsedTime)
});
$main.on('transitionend', function(e) {
console.log('transitionend:' + e.elapsedTime)
});
</script>
</body>
</html>
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