$file_dir=$totaldirectory;
     $file_name=$filename;
     //echo ''./db/''.$file_dir.$file_name;
    if (file_exists($file_dir.$file_name)){
          $file=fopen($file_dir.$file_name,''r'');
         header(''content-type:application/octet-stream'');
         header(''accept-ranges:bytes'');
         header(''content-disposition:attachment;filename=''.$file_name);
         echo fread($file,filesize($file_dir.$file_name));
         fclose($file);
         exit;
}else{
         echo ''file is not exists'';
     }