有多種方法可以將字符串分割成字符數組，我更喜歡使用擴展操作符(...):
<!DOCTYPE HTML>
<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.3.1/css/bootstrap.min.css">
<script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.min.js"></script>
<script src="https://cdn.bootcss.com/twitter-bootstrap/4.3.1/js/bootstrap.min.js"></script>
<style>
</style>
</head>
<body>
</body>
<script type="text/javascript">
const a = 'wangting'
const characters = [...a]
console.log(characters) // ["w", "a", "n", "g", "t", "i", "n", "g"]
</script>
</html>
