比如第一次请求一个文件的从0到999字节,第二次请求1000到1999字节,以此类推,每次请求1000字节的内容,然后程序通过fseek函数去取得对应的文件位置,然后输出。
$fname = './05e58c19552bb26b158f6621a6650899';
$fp = fopen($fname,'rb');
$fsize = filesize($fname);
if (isset($_SERVER['HTTP_RANGE']) && ($_SERVER['HTTP_RANGE'] != "") && preg_match("/^bytes=([0-9]+)-$/i", $_SERVER['HTTP_RANGE'], $match) && ($match[1] $start = $match[1];
} else {
$start = 0;
}
@header("Cache-control: public");
@header("Pragma: public");
if ($start > 0) {
fseek($fp, $start);
Header("HTTP/1.1 206 Partial Content");
Header("Content-Length: " . ($fsize - $start));
Header("Content-Ranges: bytes" . $start . "-" . ($fsize - 1) . "/" . $fsize);
} else {
header("Content-Length: $fsize");
Header("Accept-Ranges: bytes");
}
@header("Content-Type: application/octet-stream");
@header("Content-Disposition: attachment;filename=1.rm");
fpassthru($fp);
大家也可以看下Discuz!论坛软件的attachment.php文件是如何实现断点续传的。请看代码:
也是通过$_SERVER['HTTP_RANGE']取得用户请求的文件的range,具体的大家可以查看其源码分析下。这里我就当抛砖引玉了。
$range = 0;
if($readmod == 4) {
dheader('Accept-Ranges: bytes');
if(!emptyempty($_SERVER['HTTP_RANGE'])) {
list($range) = explode('-',(str_replace('bytes=', '', $_SERVER['HTTP_RANGE'])));
$rangesize = ($filesize - $range) > 0 ? ($filesize - $range) : 0;
dheader('Content-Length: '.$rangesize);
dheader('HTTP/1.1 206 Partial Content');
dheader('Content-Range: bytes='.$range.'-'.($filesize-1).'/'.($filesize));
}
}

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