php安全下載大檔案的實現代碼

/** * 一般檔案安全下載 * edit bbs.it-home.org */ $durl = 'file/phpcms2008_o2abf32efj883c91a.iso'; $filename = 'phpcms2008_o2abf32efj883c91a.iso'; $file = @fopen($durl, 'r'); header("Content-Type: application/octet-stream"); header("Accept-Ranges: bytes"); header("Accept-Length: ".filesize($durl)); header("Content-Disposition: attachment; filename=".$filename); echo fread($file,filesize($durl)); fclose($file); ?> 複製代碼 以上的代碼，在遇到大檔案時，超過php.ini配置的記憶體最大值的檔案時，伺服器會非常佔用CPU資源，檔案不能正常下載，只能下載幾十Kb的檔案。可以用下面的代碼來解決： /** * 大檔案安全下載的實現代碼 * edit bbs.it-home.org */ function download($url, $filename) { // 獲得檔案大小, 防止超過2G的檔案, 用sprintf來讀 $filesize = sprintf ( "%u", filesize ( $url ) ); if (! $filesize) { return; } header ( "Content-type:application/octet-stream\n" ); //application/octet-stream header ( "Content-type:unknown/unknown;" ); header ( "Content-disposition: attachment; filename=\"" . $filename . "\"" ); header ( 'Content-transfer-encoding: binary' ); if ($range = getenv ( 'HTTP_RANGE' )) { // 當有位移量的時候，採用206的斷點續傳頭 $range = explode ( '=', $range ); $range = $range [1]; header ( "HTTP/1.1 206 Partial Content" ); header ( "Date: " . gmdate ( "D, d M Y H:i:s" ) . " GMT" ); header ( "Last-Modified: " . gmdate ( "D, d M Y H:i:s", filemtime ( $url ) ) . " GMT" ); header ( "Accept-Ranges: bytes" ); header ( "Content-Length:" . ($filesize - $range) ); header ( "Content-Range: bytes " . $range . ($filesize - 1) . "/" . $filesize ); header ( "Connection: close" . "\n\n" ); } else { header ( "Content-Length:" . $filesize . "\n\n" ); $range = 0; } loadFile ( $url ); } function loadFile($filename, $retbytes = true) { $buffer = ''; $cnt = 0; $handle = fopen ( $filename, 'rb' ); if ($handle === false) { return false; } while ( ! feof ( $handle ) ) { $buffer = fread ( $handle, 1024 * 1024 ); echo $buffer; ob_flush (); flush (); if ($retbytes) { $cnt += strlen ( $buffer ); } } $status = fclose ( $handle ); if ($retbytes && $status) { return $cnt; // return num. bytes delivered like readfile() does. } return $status; } ?> 複製代碼 調用樣本： //大檔案的安全下載 download($url, $filename); 複製代碼

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