好用的phpheader下载函数
时间:2021-07-01 10:21:17
帮助过:69人阅读
/** - * 发送文件
- *
- * @param string $fileName 文件名称或路径
- * @param string $fancyName 自定义的文件名,为空则使用filename
- * @param boolean $forceDownload 是否强制下载
- * @param integer $speedLimit 速度限制,单位为字节,0为不限制,不支持windows服务器
- * @param string $$contentType 文件类型,默认为application/octet-stream
- *
- * @return boolean
- */
- function sendFile($fileName, $fancyName = '', $forceDownload = true, $speedLimit = 0, $contentType = '')
- {
- if (!is_readable($fileName))
- {
- header("HTTP/1.1 404 Not Found");
- return false;
- }
- $fileStat = stat($fileName);
- $lastModified = $fileStat['mtime'];
$md5 = md5($fileStat['mtime'] .'='. $fileStat['ino'] .'='. $fileStat['size']); - $etag = '"' . $md5 . '-' . crc32($md5) . '"';
- header('Last-Modified: ' . gmdate("D, d M Y H:i:s", $lastModified) . ' GMT');
- header("ETag: $etag");
if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= $lastModified) - {
- header("HTTP/1.1 304 Not Modified");
- return true;
- }
- if (isset($_SERVER['HTTP_IF_UNMODIFIED_SINCE']) && strtotime($_SERVER['HTTP_IF_UNMODIFIED_SINCE']) < $lastModified)
- {
- header("HTTP/1.1 304 Not Modified");
- return true;
- }
- if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && $_SERVER['HTTP_IF_NONE_MATCH'] == $etag)
- {
- header("HTTP/1.1 304 Not Modified");
- return true;
- }
- if ($fancyName == '')
- {
- $fancyName = basename($fileName);
- }
if ($contentType == '') - {
- $contentType = 'application/octet-stream';
- }
- $fileSize = $fileStat['size'];
$contentLength = $fileSize; - $isPartial = false;
- if (isset($_SERVER['HTTP_RANGE']))
- {
- if (preg_match('/^bytes=(d*)-(d*)$/', $_SERVER['HTTP_RANGE'], $matches))
- {
- $startPos = $matches[1];
- $endPos = $matches[2];
- if ($startPos == '' && $endPos == '')
- {
- return false;
- }
if ($startPos == '') - {
- $startPos = $fileSize - $endPos;
- $endPos = $fileSize - 1;
- }
- else if ($endPos == '')
- {
- $endPos = $fileSize - 1;
- }
- $startPos = $startPos < 0 ? 0 : $startPos;
- $endPos = $endPos > $fileSize - 1 ? $fileSize - 1 : $endPos;
- $length = $endPos - $startPos + 1;
- if ($length < 0)
- {
- return false;
- }
- $contentLength = $length;
- $isPartial = true;
- }
- }
// send headers - if ($isPartial)
- {
- header('HTTP/1.1 206 Partial Content');
- header("Content-Range: bytes $startPos-$endPos/$fileSize");
} - else
- {
- header("HTTP/1.1 200 OK");
- $startPos = 0;
- $endPos = $contentLength - 1;
- }
- header('Pragma: cache');
- header('Cache-Control: public, must-revalidate, max-age=0');
- header('Accept-Ranges: bytes');
- header('Content-type: ' . $contentType);
- header('Content-Length: ' . $contentLength);
if ($forceDownload) - {
- header('Content-Disposition: attachment; filename="' . rawurlencode($fancyName). '"');//汉字自动转为URL编码
- header('Content-Disposition: attachment; filename="' . $fancyName. '"');
- }
- header("Content-Transfer-Encoding: binary");
- // header函数实现文件下载
$bufferSize = 2048; - if ($speedLimit != 0)
- {
- $packetTime = floor($bufferSize * 1000000 / $speedLimit);
- }
- $bytesSent = 0;
- $fp = fopen($fileName, "rb");
- fseek($fp, $startPos);
- //fpassthru($fp);
while ($bytesSent < $contentLength && !feof($fp) && connection_status() == 0 ) - {
- if ($speedLimit != 0)
- {
- list($usec, $sec) = explode(" ", microtime());
- $outputTimeStart = ((float)$usec + (float)$sec);
- } // bbs.it-home.org
- $readBufferSize = $contentLength - $bytesSent < $bufferSize ? $contentLength - $bytesSent : $bufferSize;
- $buffer = fread($fp, $readBufferSize);
- echo $buffer;
- ob_flush();
- flush();
- $bytesSent += $readBufferSize;
if ($speedLimit != 0) - {
- list($usec, $sec) = explode(" ", microtime());
- $outputTimeEnd = ((float)$usec + (float)$sec);
$useTime = ((float) $outputTimeEnd - (float) $outputTimeStart) * 1000000; - $sleepTime = round($packetTime - $useTime);
- if ($sleepTime > 0)
- {
- usleep($sleepTime);
- }
- }
- }
- return true;
- }
- ?>
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