浏览器环境嗅探 javascript

浏览器环境检测

var inBrowser = typeof window !== 'undefined';
var UA = inBrowser && window.navigator.userAgent.toLowerCase();
var isIE = UA && /msie|trident/.test(UA);
var isIE9 = UA && UA.indexOf('msie 9.0') > 0;
var isEdge = UA && UA.indexOf('edge/') > 0;
var isAndroid = UA && UA.indexOf('android') > 0;
var isIOS = UA && /iphone|ipad|ipod|ios/.test(UA);
var isChrome = UA && /chrome\/\d+/.test(UA) && !isEdge;