js下获得客户端操作系统的函数代码(1:vista,2:windows7,3:2000,4:xp,5:2003,6:2008)

//获得客户端操作系统(1:vista,2:windows7,3:2000,4:xp,5:2003,6:2008)
function GetOSInfo(){
var _pf = navigator.platform;
var appVer = navigator.userAgent;
if(_pf == "Win32" || _pf == "Windows")
{
if(appVer.indexOf("WOW64")>-1){
_bit = "64位";
}else{
_bit = "32位";
}
if(appVer.indexOf("Windows NT 6.0") > -1 || appVer.indexOf("Windows Vista") > -1)
{
if(_bit=='64位' || appVer.indexOf("Windows Vista") > -1){
return 'Windows_vista '+_bit;
}else{
return "Unknow1";
}
}else if(appVer.indexOf("Windows NT 6.1") > -1 || appVer.indexOf("Windows 7") > -1) {
if(_bit=='32位' || appVer.indexOf("Windows 7") > -1){
return 'Windows_7 '+_bit;
}else{
return "Unknow";
}
}else {
try{
var _winName = Array('2000','XP','2003');
var _ntNum = appVer.match(/Windows NT 5.\d/i).toString();
return 'Windows_' + _winName[_ntNum.replace(/Windows NT 5.(\d)/i,"$1")]+" "+_bit;
}catch(e){return 'Windows';}
}
}else if(_pf == "Mac68K" || _pf == "MacPPC" || _pf == "Macintosh")
{
return "Mac";
}else if(_pf == "X11")
{
return "Unix";
}else if(String(_pf).indexOf("Linux") > -1)
{
return "Linux";
}else
{
return "Unknow";
}
}