利用Javascript 得到客户端的浏览器版本、操作系统等信息

<!----------javascript获取客户端ip浏览器及操作系统信息---------------->
<script type="text/javascript" src="http://fw.qq.com/ipaddress" charset="gb2312"></script>
   <script type="text/javascript">
   var ua = navigator.userAgent.toLowerCase();
var isStrict = document.compatMode == "CSS1Compat"
isOpera = ua.indexOf("opera") > -1
isChrome = ua.indexOf("chrome") > -1
isSafari = !isChrome && (/webkit|khtml/).test(ua)
isSafari3 = isSafari && ua.indexOf('webkit/5') != -1
isIE = !isOpera && ua.indexOf("msie") > -1
//isIE7 = !isOpera && ua.indexOf("msie 7") > -1
//isIE8 = !isOpera && ua.indexOf("msie 8") > -1
isGecko = !isSafari && !isChrome && ua.indexOf("gecko") > -1
isGecko3 = isGecko && ua.indexOf("rv:1.9") > -1
isBorderBox = isIE && !isStrict
var isIEBrower=!!window.ActiveXObject;
var isIE6=isIEBrower&&!window.XMLHttpRequest;
var isIE8=isIEBrower&&!!document.documentMode;
var isIE7=isIEBrower&&!isIE6&&!isIE8;

   
isWin7 = ua.indexOf("nt 6.1") > -1
isVista = ua.indexOf("nt 6.0") > -1
isWin2003 = ua.indexOf("nt 5.2") > -1
isWinXp = ua.indexOf("nt 5.1") > -1
isWin2000 = ua.indexOf("nt 5.0") > -1
isWindows = (ua.indexOf("windows") != -1 || ua.indexOf("win32") != -1)
isMac = (ua.indexOf("macintosh") != -1 || ua.indexOf("mac os x") != -1)
isAir = (ua.indexOf("adobeair") != -1)
isLinux = (ua.indexOf("linux") != -1)
var sys = "";
var broser = "";
if(isIE){
broser = "IE 6";
}else if(isIE7){
broser = "IE 7";
}else if(isIE8){
broser = "IE 8";
}else if(isOpera){
broser = "Opera";
}else if(isChrome){
broser = "Chrome";
}else if(isSafari){
broser = "Safari";
}else if(isSafari3){
broser = "Safari3";
}else{
broser = "Unknow";
}
if(isWin7){
sys = "Windows 7";
}else if(isVista){
sys = "Vista";
}else if(isWinXp){
sys = "Windows xp";
}else if(isWin2003){
sys = "Windows 2003";
}else if(isWin2000){
sys = "Windows 2000";
}else if(isWindows){
sys = "Windows";
}else if(isMac){
sys = "Macintosh";
}else if(isAir){
sys = "Adobeair";
}else if(isLinux){
sys = "Linux";
}else{
sys = "Unknow";
}
    window.onload=function()
    {
   document.getElementById("ip").innerHTML=IPData[0];
   document.getElementById("province").innerHTML=IPData[2];
   document.getElementById("city").innerHTML=IPData[3];
   document.getElementById("browser").innerHTML=broser;
   document.getElementById("sys").innerHTML=sys;
    }
   </script>