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>