php - PHP - 如何打开按文件类型在页面上流式传输的文件

Question

我想在不知道文件名或位置的情况下使用 PHP 按文件类型下载文件，这可能吗？该文件将由另一个正在流式传输该文件的 HTML 页面打开/包含。

我要制作的脚本将能够通过单独的 HTML 页面找到流/打开/包含的特定文件类型的所有文件的 URL（对不起，我不知道正确的术语）。

因此 PHP 脚本必须打开页面，确定该页面正在流式传输哪些文件，并选择具有正确文件类型的文件。那是我不知道如何写的部分，或者即使可能。

如果这不能很好地解释问题，我会添加更多。

Answer 1

如果您正在寻找适用于特定 html 页面的解决方案，那么您应该手动处理 html 并提取您需要的内容。

如果你想要一个适用于所有网页的通用解决方案......我认为唯一真正好的工作解决方案是挂钩原始网络数据，例如通过数据包嗅探器，然后让你的 php 脚本告诉安装在您的服务器上的网络浏览器要加载哪个网页。原因是媒体流通常涉及浏览器插件（java、flash、silverlight 等）或 javascript。在大多数情况下，它们需要在生成所需的 url 之前执行，因为 url 可能是从数据片段中组装而成的，或者 url 可能位于需要首先下载的外部文件中……可能性是很多的。

但是......网络浏览器可以解决这一切。让它开始流式传输一秒钟，然后您一直通过数据包嗅探器观看并寻找您感兴趣的 mime 类型，它的 url 将在数据中，所有这些都已解析并为您准备好。

再三考虑——忘记数据包嗅探器。只需编写一个浏览器扩展程序。如果萤火虫可以看到所有被请求的网址，那么您的扩展程序也可以。firebug 也是开源的，所以你可以看到他们是如何做到的。让您的扩展程序将 url 发送到本地文件或脚本。

仅供参考 - 这是一个经验丰富的程序员的任务，而不是初学者。

Answer 2

确定文件类型的最佳方法是检查文件的前几个字节——称为 [magic bytes]。

<?php
      $file = "/path/to/file";

    // in PHP 4, we can do:
    $fhandle = finfo_open(FILEINFO_MIME);
    $mime_type = finfo_file($fhandle,$file); // e.g. gives "image/jpeg" 

    // in PHP 5, we can do:

    $file_info = new finfo(FILEINFO_MIME);  // object oriented approach!
    $mime_type = $file_info->buffer(file_get_contents($file));  // e.g. gives "image/jpeg"

    switch($mime_type) {
        case "image/jpeg":
            // your actions go here...
    }
?>

这是所有 mime 类型的数组：

$mime_types = array("323" => "text/h323",
"acx" => "application/internet-property-stream",
"ai" => "application/postscript",
"aif" => "audio/x-aiff",
"aifc" => "audio/x-aiff",
"aiff" => "audio/x-aiff",
"asf" => "video/x-ms-asf",
"asr" => "video/x-ms-asf",
"asx" => "video/x-ms-asf",
"au" => "audio/basic",
"avi" => "video/x-msvideo",
"axs" => "application/olescript",
"bas" => "text/plain",
"bcpio" => "application/x-bcpio",
"bin" => "application/octet-stream",
"bmp" => "image/bmp",
"c" => "text/plain",
"cat" => "application/vnd.ms-pkiseccat",
"cdf" => "application/x-cdf",
"cer" => "application/x-x509-ca-cert",
"class" => "application/octet-stream",
"clp" => "application/x-msclip",
"cmx" => "image/x-cmx",
"cod" => "image/cis-cod",
"cpio" => "application/x-cpio",
"crd" => "application/x-mscardfile",
"crl" => "application/pkix-crl",
"crt" => "application/x-x509-ca-cert",
"csh" => "application/x-csh",
"css" => "text/css",
"dcr" => "application/x-director",
"der" => "application/x-x509-ca-cert",
"dir" => "application/x-director",
"dll" => "application/x-msdownload",
"dms" => "application/octet-stream",
"doc" => "application/msword",
"dot" => "application/msword",
"dvi" => "application/x-dvi",
"dxr" => "application/x-director",
"eps" => "application/postscript",
"etx" => "text/x-setext",
"evy" => "application/envoy",
"exe" => "application/octet-stream",
"fif" => "application/fractals",
"flr" => "x-world/x-vrml",
"gif" => "image/gif",
"gtar" => "application/x-gtar",
"gz" => "application/x-gzip",
"h" => "text/plain",
"hdf" => "application/x-hdf",
"hlp" => "application/winhlp",
"hqx" => "application/mac-binhex40",
"hta" => "application/hta",
"htc" => "text/x-component",
"htm" => "text/html",
"html" => "text/html",
"htt" => "text/webviewhtml",
"ico" => "image/x-icon",
"ief" => "image/ief",
"iii" => "application/x-iphone",
"ins" => "application/x-internet-signup",
"isp" => "application/x-internet-signup",
"jfif" => "image/pipeg",
"jpe" => "image/jpeg",
"jpeg" => "image/jpeg",
"jpg" => "image/jpeg",
"js" => "application/x-javascript",
"latex" => "application/x-latex",
"lha" => "application/octet-stream",
"lsf" => "video/x-la-asf",
"lsx" => "video/x-la-asf",
"lzh" => "application/octet-stream",
"m13" => "application/x-msmediaview",
"m14" => "application/x-msmediaview",
"m3u" => "audio/x-mpegurl",
"man" => "application/x-troff-man",
"mdb" => "application/x-msaccess",
"me" => "application/x-troff-me",
"mht" => "message/rfc822",
"mhtml" => "message/rfc822",
"mid" => "audio/mid",
"mny" => "application/x-msmoney",
"mov" => "video/quicktime",
"movie" => "video/x-sgi-movie",
"mp2" => "video/mpeg",
"mp3" => "audio/mpeg",
"mpa" => "video/mpeg",
"mpe" => "video/mpeg",
"mpeg" => "video/mpeg",
"mpg" => "video/mpeg",
"mpp" => "application/vnd.ms-project",
"mpv2" => "video/mpeg",
"ms" => "application/x-troff-ms",
"mvb" => "application/x-msmediaview",
"nws" => "message/rfc822",
"oda" => "application/oda",
"p10" => "application/pkcs10",
"p12" => "application/x-pkcs12",
"p7b" => "application/x-pkcs7-certificates",
"p7c" => "application/x-pkcs7-mime",
"p7m" => "application/x-pkcs7-mime",
"p7r" => "application/x-pkcs7-certreqresp",
"p7s" => "application/x-pkcs7-signature",
"pbm" => "image/x-portable-bitmap",
"pdf" => "application/pdf",
"pfx" => "application/x-pkcs12",
"pgm" => "image/x-portable-graymap",
"pko" => "application/ynd.ms-pkipko",
"pma" => "application/x-perfmon",
"pmc" => "application/x-perfmon",
"pml" => "application/x-perfmon",
"pmr" => "application/x-perfmon",
"pmw" => "application/x-perfmon",
"pnm" => "image/x-portable-anymap",
"pot" => "application/vnd.ms-powerpoint",
"ppm" => "image/x-portable-pixmap",
"pps" => "application/vnd.ms-powerpoint",
"ppt" => "application/vnd.ms-powerpoint",
"prf" => "application/pics-rules",
"ps" => "application/postscript",
"pub" => "application/x-mspublisher",
"qt" => "video/quicktime",
"ra" => "audio/x-pn-realaudio",
"ram" => "audio/x-pn-realaudio",
"ras" => "image/x-cmu-raster",
"rgb" => "image/x-rgb",
"rmi" => "audio/mid",
"roff" => "application/x-troff",
"rtf" => "application/rtf",
"rtx" => "text/richtext",
"scd" => "application/x-msschedule",
"sct" => "text/scriptlet",
"setpay" => "application/set-payment-initiation",
"setreg" => "application/set-registration-initiation",
"sh" => "application/x-sh",
"shar" => "application/x-shar",
"sit" => "application/x-stuffit",
"snd" => "audio/basic",
"spc" => "application/x-pkcs7-certificates",
"spl" => "application/futuresplash",
"src" => "application/x-wais-source",
"sst" => "application/vnd.ms-pkicertstore",
"stl" => "application/vnd.ms-pkistl",
"stm" => "text/html",
"svg" => "image/svg+xml",
"sv4cpio" => "application/x-sv4cpio",
"sv4crc" => "application/x-sv4crc",
"t" => "application/x-troff",
"tar" => "application/x-tar",
"tcl" => "application/x-tcl",
"tex" => "application/x-tex",
"texi" => "application/x-texinfo",
"texinfo" => "application/x-texinfo",
"tgz" => "application/x-compressed",
"tif" => "image/tiff",
"tiff" => "image/tiff",
"tr" => "application/x-troff",
"trm" => "application/x-msterminal",
"tsv" => "text/tab-separated-values",
"txt" => "text/plain",
"uls" => "text/iuls",
"ustar" => "application/x-ustar",
"vcf" => "text/x-vcard",
"vrml" => "x-world/x-vrml",
"wav" => "audio/x-wav",
"wcm" => "application/vnd.ms-works",
"wdb" => "application/vnd.ms-works",
"wks" => "application/vnd.ms-works",
"wmf" => "application/x-msmetafile",
"wps" => "application/vnd.ms-works",
"wri" => "application/x-mswrite",
"wrl" => "x-world/x-vrml",
"wrz" => "x-world/x-vrml",
"xaf" => "x-world/x-vrml",
"xbm" => "image/x-xbitmap",
"xla" => "application/vnd.ms-excel",
"xlc" => "application/vnd.ms-excel",
"xlm" => "application/vnd.ms-excel",
"xls" => "application/vnd.ms-excel",
"xlt" => "application/vnd.ms-excel",
"xlw" => "application/vnd.ms-excel",
"xof" => "x-world/x-vrml",
"xpm" => "image/x-xpixmap",
"xwd" => "image/x-xwindowdump",
"z" => "application/x-compress",
"zip" => "application/zip");

在这里检查： 在 php 中识别文件类型的最佳方法