新写PHP HTTP断点续传类文件代码

一个支持断点续传的PHP文件下载类文件，调用方法简单，类代码简洁，可记忆上次的下载的节点，实现累积下载，类名称download，类代码如下：

function download($path,$file) {
$real = $path.\'/\'.$file;
if(!file_exists($real)) {
    return false;
}
$size = filesize($real);
$size2 = $size-1;
$range = 0;
if(isset($_SERVER[\'HTTP_RANGE\'])) {
   header(\'HTTP /1.1 206 Partial Content\');
   $range = str_replace(\'=\',\'-\',$_SERVER[\'HTTP_RANGE\']);
   $range = explode(\'-\',$range);
   $range = trim($range[1]);
   header(\'Content-Length:\'.$size);
   header(\'Content-Range: bytes \'.$range.\'-\'.$size2.\'/\'.$size);
} else {
   header(\'Content-Length:\'.$size);
   header(\'Content-Range: bytes 0-\'.$size2.\'/\'.$size);
}
header(\'Accenpt-Ranges: bytes\');
header(\'application/octet-stream\');
header("Cache-control: public");
header("Pragma: public");
//解决在IE中下载时中文乱码问题
$ua = $_SERVER[\'HTTP_USER_AGENT\'];
if(preg_match(\'/MSIE/\',$ua)) {
    $ie_filename = str_replace(\'+\',\'%20\',urlencode($file));
    header(\'Content-Dispositon:attachment;filename=\'.$ie_filename);
} else {
    header(\'Content-Dispositon:attachment;filename=\'.$file);
}
$fp = fopen($real,\'rb+\');
fseek($fp,$range);
  while(!feof($fp)) {
     set_time_limit(0);
     print(fread($fp,1024));
     flush();
     ob_flush();
  }
  fclose($fp);
}

/**
　　* 参数说明：
　　* @param string $path: 文件路径
　　* @param string $file: 文件名称
　　* @return void
*/