Page Refresh in PhP After .xlsx Download - php

Question

On my site, if a user chooses to download a file, I set a session variable called $step to "downloadEnd" and my PhP code downloads a template file using the following code:
if ($step == "downloadEnd") {
$file = "Template.xlsx";
header('Content-Description: File Transfer');
header('Content-Type: ' . $mime);
header("Content-Transfer-Encoding: Binary");
header("Content-disposition: attachment; filename=\"" . basename($file) . "\"");
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
readfile($file);
exit();
$step = "nextStep"; // THIS IS THE LINE THAT DOES NOT EXECUTE
}
if ($step == "nextStep") {
// New Information Rendered to the User
}
The above code works, EXCEPT, that the last line of the first does not appear to 'execute'. In other words, after the download is complete, I want the user to see a new page with new text which is in a separate if statement ... if ($step == "downloadStart") ... but it never gets there. I believe it is because I need to somehow 'trick' the server into thinking there has been another user POST from the browser to the server AFTER the file downloads so that PhP iterates through all the 'if' statements and renders the new information to the user. I cannot seem to find a way to either: (i) have PhP trigger a page refresh after the file is done downloading; or (ii) trick the server into thinking it needs to refresh the page once the file is done. Any help would be appreciated.
I should add that I know the exit() at the end stops the PhP script from executing, but if you omit that line of code, the .xlsx file will be corrupted. I should also add that I tried the alternative fopen($file), fread($file), fclose($file) and that too gave me a corrupted .xlsx download, which is a problem others appear to have encountered as evidenced by other posts on Stack Overflow.

Answer 1

I think I see what your problem is. By running exit() you tell PHP to stop what it's doing. Try the following code:
if ($step == "downloadEnd") {
$file = "Template.xlsx";
header('Content-Description: File Transfer');
header('Content-Type: ' . $mime);
header("Content-Transfer-Encoding: Binary");
header("Content-disposition: attachment; filename=\"" . basename($file) . "\"");
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
readfile($file);
$step = "nextStep"; // THIS IS THE LINE THAT DOES NOT EXECUTE
}
if ($step == "nextStep") {
// New Information Rendered to the User
}
Also, you might want to look into JavaScript for refreshing the page after a document has downloaded.
Edit
If you are wanting to show this like a "click link if file did not properly download" page would be then the following should work:
if ($step == "downloadEnd") {
$fileURL = "https://example.com/path/to/Template.xlsx";
echo('<script>window.open("' . $fileURL . '", "_blank");</script>');
$step = "nextStep";
}
if ($step == "nextStep") {
// New Information Rendered to the User
}
You can use something like ob_end() or ob_end_clean() but it would be better to put the new information on a separate page and redirect the user there with echo('<script>window.location.replace("new.php")</script>'). Hope that helped! Also, PHP is a server-side language and therefore cannot tell when a file has finished downloading on the client.