js判断浏览器类型，设备类型

var os = function () {
 ??var ua = navigator.userAgent.toLowerCase(),
 ?????isAndroid = /(?:android)/.test(ua),
 ?????isWeChat = /(?:micromessenger)/.test(ua),
 ?????isQQ = /(?:qq)/.test(ua),
 ?????isWeiBo = /(?:weibo)/.test(ua),
 ?????isTablet = /(?:ipad|playbook)/.test(ua) || (isAndroid && !/(?:mobile)/.test(ua)),
 ?????isPhone = /(?:iphone)/.test(ua) && !isTablet,
 ?????isPc = !isPhone && !isAndroid && !isTablet;
 ??return {
 ?????isTablet: isTablet,// 平板
 ?????isPhone: isPhone, // 苹果
 ?????isAndroid: isAndroid, //安卓
 ?????isWeChat: isWeChat, //微信
 ?????isQQ: isQQ, // QQ
 ?????isWeiBo: isWeiBo, // 微博
 ?????isPc: isPc // PC端
 ??};
}();

//使用
if (os.isPc) {
 ??console.log(‘isPc :‘);
} else if (os.isAndroid) {
 ??console.log(‘isAndroid‘);
}
else if (os.isPhone) {
 ??console.log(‘isPhone‘);
}