在舊金山灣區時間與北京時間轉換，用Javascript方便地實現時區轉換例子一文中示範了怎樣用moment.js做時間的時區轉換的例子。例子里下載了moment.js和moment-timezone-with-data.js，如官方文檔所說的，加載如下
<script src="moment.js"></script>
<script src="moment-timezone-with-data.js"></script><script src="moment.js"></script>
<script src="moment-timezone-with-data.js"></script>那麼能不能不下載，直接用CDN呢？也是可以的
<script type="text/javascript" src="https://momentjs.com/downloads/moment.js">
</script>
<script type="text/javascript" src="https://momentjs.com/downloads/moment-timezone-with-data.js">
</script><script type="text/javascript" src="https://momentjs.com/downloads/moment.js">
</script>
<script type="text/javascript" src="https://momentjs.com/downloads/moment-timezone-with-data.js">
</script>那麼之前的例子就變成如下
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="https://momentjs.com/downloads/moment.js">
</script>
<script type="text/javascript" src="https://momentjs.com/downloads/moment-timezone-with-data.js">
</script>
</head>
<body>
<script>
const sftime = moment().tz('America/Los_Angeles');
const bjtime = moment(sftime).tz('Asia/Shanghai');
// check result
const fmt = 'hh:mm:ss a z YYYY-MM-DD';
console.log(sftime.format(fmt));
console.log(bjtime.format(fmt));
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="https://momentjs.com/downloads/moment.js">
</script>
<script type="text/javascript" src="https://momentjs.com/downloads/moment-timezone-with-data.js">
</script>
</head>
<body>
<script>
const sftime = moment().tz('America/Los_Angeles');
const bjtime = moment(sftime).tz('Asia/Shanghai');
// check result
const fmt = 'hh:mm:ss a z YYYY-MM-DD';
console.log(sftime.format(fmt));
console.log(bjtime.format(fmt));
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript" src="https://momentjs.com/downloads/moment.js">
</script>
<script type="text/javascript" src="https://momentjs.com/downloads/moment-timezone-with-data.js">
</script>
</head>
<body>
<script>
const sftime = moment().tz('America/Los_Angeles');
const bjtime = moment(sftime).tz('Asia/Shanghai');
// check result
const fmt = 'hh:mm:ss a z YYYY-MM-DD';
console.log(sftime.format(fmt));
console.log(bjtime.format(fmt));
</script>
</body>
</html>
使用CDN就不再需要把兩個js文件下載和html文件放一起，而加載地址改成CDN的URL。使用上和原來一樣。
