PHP小工具

防SQL注入
function clean($input)
{
  if (is_array($input))
  {
    foreach ($input as $key => $val)
     {
      $output[$key] = clean($val);
    }
  }
  else
  {
    $output = (string) $input;
    if (get_magic_quotes_gpc())
    {
      $output = stripslashes($output);
    }
    $output = htmlentities($output, ENT_QUOTES, 'UTF-8');
  }
  return $output;
}

根据IP确定用户地理位置
function detect_city($ip) {

    $default = 'UNKNOWN';

    $curlopt_useragent = 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2) Gecko/20100115 Firefox/3.6 (.NET CLR 3.5.30729)';

    $url = 'http://ipinfodb.com/ip_locator.php?ip=' . urlencode($ip);
    $ch = curl_init();

    $curl_opt = array(
      CURLOPT_FOLLOWLOCATION => 1,
      CURLOPT_HEADER   => 0,
      CURLOPT_RETURNTRANSFER => 1,
      CURLOPT_USERAGENT  => $curlopt_useragent,
      CURLOPT_URL    => $url,
      CURLOPT_TIMEOUT     => 1,
      CURLOPT_REFERER     => 'http://' . $_SERVER['HTTP_HOST'],
    );

    curl_setopt_array($ch, $curl_opt);

    $content = curl_exec($ch);

    if (!is_null($curl_info)) {
      $curl_info = curl_getinfo($ch);
    }

    curl_close($ch);

    if ( preg_match('{<li>City : ([^<]*)</li>}i', $content, $regs) ) {
      $city = $regs[1];
    }
    if ( preg_match('{<li>State/Province : ([^<]*)</li>}i', $content, $regs) ) {
      $state = $regs[1];
    }

    if( $city!='' && $state!='' ){
     $location = $city . ', ' . $state;
     return $location;
    }else{
     return $default;
    }
  }

确定任意图片的主导颜色
function dominant_color($image)
{
　　$i = imagecreatefromjpeg($image);
　　for ($x=0;$x<imagesx($i);$x++) {
  　　　for ($y=0;$y<imagesy($i);$y++) {
    　　　　$rgb = imagecolorat($i,$x,$y);
    　　　　$r  = ($rgb >> 16) & 0xFF;
    　　　　$g  = ($rgb >> & 0xFF;
    　　　　$b  = $rgb & 0xFF;
    　　　　$rTotal += $r;
    　　　　$gTotal += $g;
    　　　　$bTotal += $b;
    　　　　$total++;
  　　 }
　　}
　　$rAverage = round($rTotal/$total);
　　$gAverage = round($gTotal/$total);
　　$bAverage = round($bTotal/$total);
　　return ["r"=>$rAverage,"g"=>$gAverage,"b"=>$bAverage];
}

强制下载文件
function force_download($file)
{
  $dir   = "../log/exports/";
  if ((isset($file))&&(file_exists($dir.$file))) {
    header("Content-type: application/force-download");
    header('Content-Disposition: inline; filename="' . $dir.$file . '"');
    header("Content-Transfer-Encoding: Binary");
    header("Content-length: ".filesize($dir.$file));
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="' . $file . '"');
    readfile("$dir$file");
  } else {
    echo "No file selected";
  }
}

解压图片
function unzip($location,$newLocation)
{
    if(exec("unzip $location",$arr)){
      mkdir($newLocation);
      for($i = 1;$i< count($arr);$i++){
        $file = trim(preg_replace("~inflating: ~","",$arr[$i]));
        copy($location.'/'.$file,$newLocation.'/'.$file);
        unlink($location.'/'.$file);
      }
      return TRUE;
    }else{
      return FALSE;
    }
}

缩放图片
function resize_image($filename, $tmpname, $xmax, $ymax)
{
  $ext = explode(".", $filename);
  $ext = $ext[count($ext)-1]; 

  if($ext == "jpg" || $ext == "jpeg")
    $im = imagecreatefromjpeg($tmpname);
  elseif($ext == "png")
    $im = imagecreatefrompng($tmpname);
  elseif($ext == "gif")
    $im = imagecreatefromgif($tmpname); 

  $x = imagesx($im);
  $y = imagesy($im); 

  if($x <= $xmax && $y <= $ymax)
    return $im; 

  if($x >= $y) {
    $newx = $xmax;
    $newy = $newx * $y / $x;
  }
  else {
    $newy = $ymax;
    $newx = $x / $y * $newy;
  } 

  $im2 = imagecreatetruecolor($newx, $newy);
  imagecopyresized($im2, $im, 0, 0, 0, 0, floor($newx), floor($newy), $x, $y);
  return $im2;
}

检测用户浏览器语言
function get_client_language($availableLanguages, $default='en'){
  if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
    $langs=explode(',',$_SERVER['HTTP_ACCEPT_LANGUAGE']);
    foreach ($langs as $value){
      $choice=substr($value,0,2);
      if(in_array($choice, $availableLanguages)){
        return $choice;
      }
    }
  }
  return $default;
}