Php下载脚本输出损坏的文件 [英] Php download script outputs corrupted file

问题描述

我正在PHP中为CMS建立一个文件下载类，我注意到它以不同的编码格式输出文件。我尝试用readfile，file_get_contents，fread，但似乎都在做同样的事情。它就像与输出缓冲有关的东西。

以png格式的一个示例图像文件我使用脚本下载的图像文件似乎在使用notepad ++更改Encoding后起作用UTF到ASCII

这些是我到目前为止采取的步骤：

 <$ c 
 header（'Expires：0'）; 
头（'缓存控制： 
 header（'Cache-Control：private'，false）; 
 header（'Content-Type：'。$ mime ）; 
 header（'Content-Disposition：attachment; filename ='。basename（$ file）。'''）; 
 header（'Content-Transfer-Encoding：binary'）; 
 header（'Transfer-Encoding：binary'）; 
 header（'Content-Description：File Transfer'）; 
 header（'Content-Encoding：chunked'）; 
 header 'connection：closed'）; 
 @readfile（$ this-> file）; 
  

我发现了：

  $ file = fopen（$ this-> file，'r'）; 
 $ read = fread（$ file，filesize（$ this-> file） ）; 
 print（$ read）; 
  

我做了file_get_contents（）;

  $ read = file_get_contents（$ this-> file）; 
 print（$ read）; 
  

所有这些步骤都将文件发送到下载对话框。但它不会输出文件。而这会影响我尝试使用脚本下载的任何文件。

我做错了什么？

解决方案

尝试运行一个 ob_start（）作为脚本中的第一件事，写东西，编辑头文件，然后只要您希望将内容发送到用户的浏览器，ob_flush（）和 ob_clean（）

这是适用于我..

  if（file_exists（$ file））{
 header （'内容描述：文件传输'）; 
 header（'Content-Type：application / octet-stream'）; 
 header（'Content-Disposition：attachment; filename ='。basename（$ file））; 
 header（'Content-Transfer-Encoding：binary'）; 
 header（'Expires：0'）; 
 header（'Cache-Control：must-revalidate，post-check = 0，pre-check = 0'）; 
 header（'Pragma：public'）; 
 header（'Content-Length：'。filesize（$ file））; 
 ob_clean（）; 
 flush（）; 
 readfile（$ file）; 
退出; 
} 
  

希望这有帮助..

I was building a file download Class for my CMS in PHP, at a time I noticed it outputs files in a different Encoding format. I tried with readfile, file_get_contents,fread but all seem to be doing the same thing. It"s like something that has to do with output buffering.

An example image file in png format I downloaded using the script seems to work after changing the Encoding using notepad++ from UTF to ASCII

These are the steps i've taken so far:

$mime = http::get_file_mime();
header('Pragma: public');   
header('Expires: 0');       
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Cache-Control: private',false);
header('Content-Type: '.$mime);
header('Content-Disposition: attachment; filename="'.basename($file).'"');
header('Content-Transfer-Encoding: binary');
header('Transfer-Encoding: binary');
header('Content-Description: File Transfer');
header('Content-Encoding: chunked');
header('Connection: closed');
@readfile($this->file);

I did fread:

$file = fopen($this->file,'r');
$read = fread($file,filesize($this->file));
print($read);

I did file_get_contents();

$read = file_get_contents($this->file);
print($read);

All of these steps sends the file to the download dialog. But it doesnt output the file as it is. And this affects any file i try to download with the script.

What am i doing wrong ?

解决方案

Try running an ob_start() as the first thing in your script, write stuff, edit your headers and then ob_flush() and ob_clean() whenever you want your content to be sent to the user's browser.

This is worked for me..

if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename='.basename($file));
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    ob_clean();
    flush();
    readfile($file);
    exit;
}

Hope this helps..

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