要區分用戶是通過"微信內置瀏覽器"還是"原生瀏覽器"打開的WebApp, 可以通過navigator.userAgent來進行判斷.
以下是對各種平台上微信內置瀏覽器和原生瀏覽器UA的對比
PC版微信:
Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36 MicroMessenger/6.5.2.501 NetType/WIFI WindowsWechat
PC Chrome:
Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.110 Safari/537.36
iPhone版微信:
Mozilla/5.0 (iPhone; CPU iPhone OS 9_3 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Mobile/13E233 MicroMessenger/6.3.15 NetType/WIFI Language/zh_CN
iPhone Safari:
Mozilla/5.0 (iPhone; CPU iPhone OS 9_3 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13E233 Safari/601.1
Android版微信:
Mozilla/5.0 (Linux; Android 5.0.1; GT-I9502 Build/LRX22C; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/43.0.2357.121 Mobile Safari/537.36 MicroMessenger/6.1.0.78_r1129455.543 NetType/WIFI
Android (Samsung S4) 默認瀏覽器:
Mozilla/5.0 (Linux; Android 5.0.1; SAMSUNG GT-I9502 Build/LRX22C) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/2.1 Chrome/34.0.1847.76 Mobile Safari/537.36
注: Mi4刷的WinPhone系統...
WinPhone版微信:
Mozilla/5.0 (Windows Phone 8.1; ARM; Trident/8.0; Touch; rv:11.0; WebBrowser/8.1; IEMobile/11.0; XIAOMITEST; MI4) like Gecko false
WinPhone 默認瀏覽器:
Mozilla.5.0 (Windows Phone 10.0; Android 4.2.1; XIAOMITEST; MI4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Mobile Safari/537.36 Edge/13.10586 false
綜上, 在iPhone和Android上, 可以用micromessenger來判斷, 而在WinPhone上, 可以用webbrowser來判斷.
var isInWeChat = /(micromessenger|webbrowser)/.test(navigator.userAgent.toLocaleLowerCase());
如果你感興趣的話, 可以通過打開 http://whatsmyuseragent.com/ 查看你的UA.