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"; 
 } 
}

<script type="text/javascript">
//获取客户端操作系统类型 
function detectOS() { 
  var sUserAgent = navigator.userAgent; 
  var isWin = (navigator.platform == "Win32") || (navigator.platform == "Windows"); 
  var isMac = (navigator.platform == "Mac68K") || (navigator.platform == "MacPPC") || (navigator.platform == "Macintosh") || (navigator.platform == "MacIntel"); 
  if (isMac) return "Mac"; 
  var isUnix = (navigator.platform == "X11") && !isWin && !isMac; 
  if (isUnix) return "Unix"; 
  var isLinux = (String(navigator.platform).indexOf("Linux") > -1); 
  if (isLinux) return "Linux"; 
  if (isWin) { 
    var isWin2K = sUserAgent.indexOf("Windows NT 5.0") > -1 || sUserAgent.indexOf("Windows 2000") > -1; 
    if (isWin2K) return "Win2000"; 
    var isWinXP = sUserAgent.indexOf("Windows NT 5.1") > -1 || sUserAgent.indexOf("Windows XP") > -1; 
    if (isWinXP) return "WinXP"; 
    var isWin2003 = sUserAgent.indexOf("Windows NT 5.2") > -1 || sUserAgent.indexOf("Windows 2003") > -1; 
    if (isWin2003) return "Win2003"; 
    var isWin2003 = sUserAgent.indexOf("Windows NT 6.0") > -1 || sUserAgent.indexOf("Windows Vista") > -1; 
    if (isWin2003) return "WinVista"; 
    var isWin2003 = sUserAgent.indexOf("Windows NT 6.1") > -1 || sUserAgent.indexOf("Windows 7") > -1; 
    if (isWin2003) return "Win7"; 
  } 
  return "None"; 
} 
function locationHref(e){
 switch(e){
 case 'Mac':
 window.location.href='http://www.baidu.com';
 break;
 case 'Unix':
 window.location.href='http://tieba.baidu.com';
 break;
 case 'Linux':
 window.location.href='http://map.baidu.com';
 break;
 case 'Win2000':
 window.location.href='http://mp3.baidu.com';
 break;
 case 'WinXP':
 window.location.href='http://baike.baidu.com';
 break;
 case 'Win2003':
 window.location.href='http://zhidao.baidu.com';
 break;
 case 'WinVista':
 window.location.href='http://hi.baidu.com';
 break;
 case 'Win7':
 window.location.href='http://video.baidu.com';
 break;
 default :
 window.location.href='http://www.hao123.com/';
 break;
 }
 }
</script><script type="text/javascript">var kk=detectOS();alert(kk);/*locationHref(kk);*/</script>