js如何判断IE浏览器的版本包括IE11

IE浏览器真是个坑:从ie6以及以前IE版本,简直就是垃圾,不按照Mozilla国际组织的标准来,乱搞。搞得兼容性很差:
 
<script type="text/javascript">
var userAgent = navigator.userAgent,
rMsie = /(msies|trident.*rv:)([w.]+)/,
rFirefox = /(firefox)/([w.]+)/,
rOpera = /(opera).+version/([w.]+)/,
rChrome = /(chrome)/([w.]+)/,
rSafari = /version/([w.]+).*(safari)/;
var browser;
var version;
var ua = userAgent.toLowerCase();
function uaMatch(ua){
 var match = rMsie.exec(ua);
 if(match != null){
 return { browser : "IE", version : match[2] || "0" };
 }
 var match = rFirefox.exec(ua);
 if (match != null) {
 return { browser : match[1] || "", version : match[2] || "0" };
 }
 var match = rOpera.exec(ua);
 if (match != null) {
 return { browser : match[1] || "", version : match[2] || "0" };
 }
 var match = rChrome.exec(ua);
 if (match != null) {
 return { browser : match[1] || "", version : match[2] || "0" };
 }
 var match = rSafari.exec(ua);
 if (match != null) {
 return { browser : match[2] || "", version : match[1] || "0" };
 }
 if (match != null) {
 return { browser : "", version : "0" };
 }
}
var browserMatch = uaMatch(userAgent.toLowerCase());
if (browserMatch.browser){
 browser = browserMatch.browser;
 version = browserMatch.version;
}
document.write(browser+version); 
</script>
 
我这里有个最简单的:
原文地址:https://www.cnblogs.com/BluceLee/p/9225320.html