/服务器文件路径，下载文件名字(默认为服务器文件名)，是否许可用户下载方式(默认可选)，速度限制(默认自动)，文件类型(默认所有) 可能是服务器原因 配置较低 下载一段服务器会崩溃 下载也会停止/
public function downFile($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). '"');
} header("Content-Transfer-Encoding: binary"); $bufferSize = 2048; if ($speedLimit != 0)
{ $packetTime = floor($bufferSize * 1000000 / $speedLimit);
} $bytesSent = 0;
$fp = fopen($fileName, "rb");
fseek($fp, $startPos);
while ($bytesSent < $contentLength && !feof($fp) && connection_status() == 0 )
{ if ($speedLimit != 0) { list($usec, $sec) = explode(" ", microtime()); $outputTimeStart = ((float)$usec + (float)$sec); } $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; 

}

public function download(){

    $id = input('id');$item = Db::name('imgsubmit')->where(['id'=>$id])->find();Db::name('imgsubmit')->where(['id'=>$id])->update(['status'=>1]);$tt = ltrim($item['zip'],'uploads/');$path = config('upload_path').DS.$tt;$arr = explode('/',$path);$iname=$item['username'].'_'.$item['order_no'];///*$filename = $arr[count($arr)-1];*/$filename=$iname.'.zip';//$file  =  fopen($path, "rb");//$flag = $this->downFile($path); $flag =  $this->downloadob($path, $filename, true); // 断点续传  exit ();
}本文转自lb沫51CTO博客，原文链接：http://blog.51cto.com/13562606/2066550，如需转载请自行联系原作者