<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>用 async/await 來處理異步實例</title> <style type="text/css"> </style> </head> <body> <script type="text/javascript"> function doubleAfter2seconds(num) { return new Promise((resolve, reject) => { setTimeout(() => { resolve(2 * num) }, 2000); } ) } async function timeout() { var result = await doubleAfter2seconds(30); return result; } timeout().then(result => { console.log(result); }) console.log('雖然在後面,可是我先執行'); </script> </body> </html>