var isMac = /macintosh|mac os x/i.test(navigator.userAgent);标签：iPad,判断,浏览器,var,test,userAgent,navigator,设备 From： https://www.cnblogs.com/yycc11/p/16788090.html
var isWindows = /windows|win32/i.test(navigator.userAgent);
var isAndriod = /andriod/i.test(navigator.userAgent);
var isIos = /(iPhone|iPad|iPod|iOS)/i.test(navigator.userAgent);
var isWeChat = /MicroMessenger/i.test(navigator.userAgent);