代码在ext里的src\core\ext.js下 最新的ext3.0beat1的代码如下: 代码如下: ua = navigator.userAgent.toLowerCase(), check = function(r){ return r.test(ua); }, isStrict = document.compatMode == “CSS1Compat”, isOpera = check(/opera/), isChrome = check(/chrome/), isWebKit = check(/webkit/), isSafari = !isChrome && check(/saf