<?
//====================================================
//           FileName:download.class.php
//           Summary: 文件下载类
//           Author: feifengxlq
//     Email:feifengxlq@sohu.com
//           CreateTime: 2005-7-19  
//           LastModifed:
//           copyright (c)2005 xlq.100steps.net feifengxlq@sohu.com
//   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";
}
}
?>