PHP文件下载类

<?    
//====================================================    
//   使用范例：    
// $download=new download('php,exe,html',false);    
//  if(!$download->downloadfile($filename))    
//  {    
//    echo $download->geterrormsg();    
//  }          
//====================================================    
class download{    
  var $debug=true;    
  var $errormsg='';    
  var $Filter=array();    
  var $filename='';    
  var $mineType='text/plain';    
  var $xlq_filetype=array();      function download($fileFilter='',$isdebug=true)    
  {    
    $this->setFilter($fileFilter);    
        $this->setdebug($isdebug);            
        $this->setfiletype();    
  }    
  function setFilter($fileFilter)    
  {    
    if(empty($fileFilter)) return ;    
        $this->Filter=explode(',',strtolower($fileFilter));    
  }    
  function setdebug($debug)    
  {    
    $this->debug=$debug;    
  }    
  function setfilename($filename)    
  {    
    $this->filename=$filename;    
  }    
  function downloadfile($filename)    
  {    
    $this->setfilename($filename);    
    if($this->filecheck())    
        {    
          $fn = array_pop( explode( '/', strtr( $this->filename, '\\', '/' ) ) );    
          header( "Pragma: public" );    
      header( "Expires: 0" ); // set expiration time    
      header( "Cache-Component: must-revalidate, post-check=0, pre-check=0" );    
          header( "Content-type:".$this->mineType );    
      header( "Content-Length: " . filesize( $this->filename ) );    
      header( "Content-Disposition: attachment; filename=\"$fn\"" );    
      header( 'Content-Transfer-Encoding: binary' );    
      readfile( $this->filename );    
      return true;    
        }else    
        {    
        return false;    
        }    
  }    
  function geterrormsg()    
  {    
    return $this->errormsg;    
  }    
  function filecheck()    
  {    
    $filename=$this->filename;    
        if(file_exists($filename))    
        {    
           $filetype=strtolower(array_pop(explode('.',$filename)));    
           if(in_array($filetype,$this->Filter))    
           {    
             $this->errormsg.=$filename.'不允许下载！';    
                 if($this->debug) exit($filename.'不允许下载！') ;    
                 return false;    
           }else    
           {    
             if ( function_exists( "mime_content_type" ) )    
                 {    
           $this->mineType = mime_content_type( $filename );    
         }    
                 if(empty($this->mineType))    
                 {    
                    if( isset($this->xlq_filetype[$filetype]) )  $this->mineType = $this->xlq_filetype[$filetype];    
                 }    
                 if(!empty($this->mineType))    
                   return true;    
                 else    
                 {    
                    $this->errormsg.='获取'.$filename.'文件类型时候发生错误，或者不存在预定文件类型内';    
                        if($this->debug) exit('获取文件类型出错');    
                        return false;    
                 }    
           }     
        }else    
        {    
          $this->errormsg.=$filename.'不存在!';    
          if($this->debug) exit($filename.'不存在!') ;    
          return false;    
        }    
  }    
  function setfiletype()    
  {    
    $this->xlq_filetype['chm']='application/octet-stream';    
    $this->xlq_filetype['ppt']='application/vnd.ms-powerpoint';    
    $this->xlq_filetype['xls']='application/vnd.ms-excel';    
    $this->xlq_filetype['doc']='application/msword';    
    $this->xlq_filetype['exe']='application/octet-stream';    
    $this->xlq_filetype['rar']='application/octet-stream';    
    $this->xlq_filetype['js']="javascript/js";    
    $this->xlq_filetype['css']="text/css";    
    $this->xlq_filetype['hqx']="application/mac-binhex40";    
    $this->xlq_filetype['bin']="application/octet-stream";    
    $this->xlq_filetype['oda']="application/oda";    
    $this->xlq_filetype['pdf']="application/pdf";    
    $this->xlq_filetype['ai']="application/postsrcipt";    
    $this->xlq_filetype['eps']="application/postsrcipt";    
    $this->xlq_filetype['es']="application/postsrcipt";    
    $this->xlq_filetype['rtf']="application/rtf";    
    $this->xlq_filetype['mif']="application/x-mif";    
    $this->xlq_filetype['csh']="application/x-csh";    
    $this->xlq_filetype['dvi']="application/x-dvi";    
    $this->xlq_filetype['hdf']="application/x-hdf";    
    $this->xlq_filetype['nc']="application/x-netcdf";    
    $this->xlq_filetype['cdf']="application/x-netcdf";    
    $this->xlq_filetype['latex']="application/x-latex";    
    $this->xlq_filetype['ts']="application/x-troll-ts";    
    $this->xlq_filetype['src']="application/x-wais-source";    
    $this->xlq_filetype['zip']="application/zip";    
    $this->xlq_filetype['bcpio']="application/x-bcpio";    
    $this->xlq_filetype['cpio']="application/x-cpio";    
    $this->xlq_filetype['gtar']="application/x-gtar";    
    $this->xlq_filetype['shar']="application/x-shar";    
    $this->xlq_filetype['sv4cpio']="application/x-sv4cpio";    
    $this->xlq_filetype['sv4crc']="application/x-sv4crc";    
    $this->xlq_filetype['tar']="application/x-tar";    
    $this->xlq_filetype['ustar']="application/x-ustar";    
    $this->xlq_filetype['man']="application/x-troff-man";    
    $this->xlq_filetype['sh']="application/x-sh";    
    $this->xlq_filetype['tcl']="application/x-tcl";    
    $this->xlq_filetype['tex']="application/x-tex";    
    $this->xlq_filetype['texi']="application/x-texinfo";    
    $this->xlq_filetype['texinfo']="application/x-texinfo";    
    $this->xlq_filetype['t']="application/x-troff";    
    $this->xlq_filetype['tr']="application/x-troff";    
    $this->xlq_filetype['roff']="application/x-troff";    
    $this->xlq_filetype['shar']="application/x-shar";    
    $this->xlq_filetype['me']="application/x-troll-me";    
    $this->xlq_filetype['ts']="application/x-troll-ts";    
    $this->xlq_filetype['gif']="image/gif";    
    $this->xlq_filetype['jpeg']="image/pjpeg";    
    $this->xlq_filetype['jpg']="image/pjpeg";    
    $this->xlq_filetype['jpe']="image/pjpeg";    
    $this->xlq_filetype['ras']="image/x-cmu-raster";    
    $this->xlq_filetype['pbm']="image/x-portable-bitmap";    
    $this->xlq_filetype['ppm']="image/x-portable-pixmap";    
    $this->xlq_filetype['xbm']="image/x-xbitmap";    
    $this->xlq_filetype['xwd']="image/x-xwindowdump";    
    $this->xlq_filetype['ief']="image/ief";    
    $this->xlq_filetype['tif']="image/tiff";    
    $this->xlq_filetype['tiff']="image/tiff";    
    $this->xlq_filetype['pnm']="image/x-portable-anymap";    
    $this->xlq_filetype['pgm']="image/x-portable-graymap";    
    $this->xlq_filetype['rgb']="image/x-rgb";    
    $this->xlq_filetype['xpm']="image/x-xpixmap";    
    $this->xlq_filetype['txt']="text/plain";    
    $this->xlq_filetype['c']="text/plain";    
    $this->xlq_filetype['cc']="text/plain";    
    $this->xlq_filetype['h']="text/plain";    
    $this->xlq_filetype['html']="text/html";    
    $this->xlq_filetype['htm']="text/html";    
    $this->xlq_filetype['htl']="text/html";    
    $this->xlq_filetype['rtx']="text/richtext";    
    $this->xlq_filetype['etx']="text/x-setext";    
    $this->xlq_filetype['tsv']="text/tab-separated-values";    
    $this->xlq_filetype['mpeg']="video/mpeg";    
    $this->xlq_filetype['mpg']="video/mpeg";    
    $this->xlq_filetype['mpe']="video/mpeg";    
    $this->xlq_filetype['avi']="video/x-msvideo";    
    $this->xlq_filetype['qt']="video/quicktime";    
    $this->xlq_filetype['mov']="video/quicktime";    
    $this->xlq_filetype['moov']="video/quicktime";    
    $this->xlq_filetype['movie']="video/x-sgi-movie";    
    $this->xlq_filetype['au']="audio/basic";    
    $this->xlq_filetype['snd']="audio/basic";    
    $this->xlq_filetype['wav']="audio/x-wav";    
    $this->xlq_filetype['aif']="audio/x-aiff";    
    $this->xlq_filetype['aiff']="audio/x-aiff";    
    $this->xlq_filetype['aifc']="audio/x-aiff";    
    $this->xlq_filetype['swf']="application/x-shockwave-flash";    
  }    
}    
?>