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 = /(msie\s|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：