PHP获取用户操作系统、浏览器、ip信息

<?php

// --------------------------------------------------
// 分析返回用户操作系统名称
// --------------------------------------------------
function getSystem(){
  $sys = $_SERVER['HTTP_USER_AGENT'];
  if(stripos($sys, "NT 6.1"))
     $os = "Windows 7";
  elseif(stripos($sys, "NT 6.0"))
     $os = "Windows Vista";
  elseif(stripos($sys, "NT 5.1"))
     $os = "Windows XP";
  elseif(stripos($sys, "NT 5.2"))
     $os = "Windows Server 2003";
  elseif(stripos($sys, "NT 5"))
     $os = "Windows 2000";
  elseif(stripos($sys, "NT 4.9"))
     $os = "Windows ME";
  elseif(stripos($sys, "NT 4"))
     $os = "Windows NT 4.0";
  elseif(stripos($sys, "98"))
     $os = "Windows 98";
  elseif(stripos($sys, "95"))
     $os = "Windows 95";
  elseif(stripos($sys, "Mac"))
     $os = "Mac";
  elseif(stripos($sys, "Linux"))
     $os = "Linux";
  elseif(stripos($sys, "Unix"))
     $os = "Unix";
  elseif(stripos($sys, "FreeBSD"))
     $os = "FreeBSD";
  elseif(stripos($sys, "SunOS"))
     $os = "SunOS";
  elseif(stripos($sys, "BeOS"))
     $os = "BeOS";
  elseif(stripos($sys, "OS/2"))
     $os = "OS/2";
  elseif(stripos($sys, "PC"))
     $os = "Macintosh";
  elseif(stripos($sys, "AIX"))
     $os = "AIX";
  else
     $os = "未知操作系统";
  
  return $os;
}

// --------------------------------------------------
// 分析返回用户网页浏览器名称
// --------------------------------------------------
function getBrowser(){
  $browser = $_SERVER['HTTP_USER_AGENT'];
  if(strpos(strtolower($browser),"netcaptor"))
     $exp = "NetCaptor";
  elseif(strpos(strtolower($browser),"firefox")){
     preg_match("/Firefox\/([^;)]+)+/i", $sys, $b);
     $exp = "Mozilla Firefox ".$b[1];
  }elseif(strpos(strtolower($browser),"maxthon")){
     preg_match("/MAXTHON\s+([^;)]+)+/i", $sys, $b);
     preg_match("/MSIE\s+([^;)]+)+/i", $sys, $ie);
     $exp = $b[0]." (IE".$ie[1].")";
  }elseif(strpos(strtolower($browser),"msie")){
     preg_match("/MSIE\s+([^;)]+)+/i", $sys, $ie);
     $exp = "Internet Explorer ".$ie[1];
  }elseif(strpos(strtolower($browser),"netscape"))
     $exp = "Netscape";
  elseif(strpos(strtolower($browser),"opera"))
     $exp = "Opera";
  else
     $exp = "未知浏览器";
    
  return $exp;
}

// --------------------------------------------------
// 分析返回用户ip
// --------------------------------------------------
function getIp(){
  $ip = '';
  if ($_SERVER["HTTP_X_FORWARDED_FOR"]){
    $ip = $_SERVER["HTTP_X_FORWARDED_FOR"];
  }elseif ($_SERVER["HTTP_CLIENT_IP"]){
    $ip = $_SERVER["HTTP_CLIENT_IP"];
  }elseif ($_SERVER["REMOTE_ADDR"]){
    $ip = $_SERVER["REMOTE_ADDR"];
  }elseif (getenv("HTTP_X_FORWARDED_FOR")){
    $ip = getenv("HTTP_X_FORWARDED_FOR");
  }elseif (getenv("HTTP_CLIENT_IP")){
    $ip = getenv("HTTP_CLIENT_IP");
  }elseif (getenv("REMOTE_ADDR")){
    $ip = getenv("REMOTE_ADDR");
  }else{
    $ip = "unknown";
  }
  
  return $ip;
}

?>