PHP force downloading .xlsx file corrupt

问题

I am working on a site that allows teachers to upload documents and students download them. However, there is a problem. Microsoft Word (.docx) files download perfectly, but when downloading an excel (xlsx) file, excel gives a "This file is corrupt and cannot be opened" dialog. Any help with this would be greatly appreciated!

My download code is as follows:

case 'xlsx':

    header('Content-type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
    header('Content-Disposition: attachment; filename="' . $filename . '"');
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Pragma: no-cache');
    readfile('./uploads/resources/courses/' . $filename);

break;

回答1:

this works fine on my local xampp setup regardless of extension so from my point of view no case statement is needed unless i'm missing something

i've tested with docx, accdb, xlsx, mp3, anything ...

$filename = "equiv1.xlsx";

header('Content-type: application/octet-stream');
header('Content-Disposition: attachment; filename="' . $filename . '"');
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Pragma: no-cache');

回答2:

I have this problem and was the BOM.

How to notice it

unzip: Checking the output file with unzip, I saw a warning at the second line.

$ unzip -l file.xlsx 
Archive:   file.xlsx
warning file:  3 extra bytes at beginning or within zipfile
...

xxd (hex viewer): I saw the first 5 bytes with the following command

head -c5 file.xlsx | xxd -g 1
0000000: ef bb bf 50 4b                             PK...

Notice the 3 first bytes ef bb bf that's BOM!

Why?

Maybe a php file with BOM or a previous output from a library.

You have to find where is the file or command with the BOM, In my case and right now, I don't have time to find it, but I solve this with output buffer.

<?php
ob_start();

// ... code, includes, etc

ob_get_clean();
// headers ...
readfile($file);

回答3:

try this:

header("Content-Disposition: attachment; filename=\"$filename\"");
header("Content-Type: application/vnd.ms-excel");

回答4:

try:

<?
//disable gzip
@apache_setenv('no-gzip', 1); 
//set download attachment
header('Content-Disposition: attachment;filename="filename.xlsx"');
//clean the output buffer 
ob_clean(); 
//output file
readfile('filepath/filename.xlsx');
//discard any extra characters after this line
exit; 
?>

回答5:

Try adding a additional header

header('Content-Length: ' . filesize('./uploads/resources/courses/' . $filename));

来源：https://stackoverflow.com/questions/13938190/php-force-downloading-xlsx-file-corrupt