download – Generate Filename from Field (Array)?

[MBM]

I have a download script that generates a filename with a prefix followed by a random number to store a HTML page as a png file using html2canvas. Is it possible to generate the filename using the name field in a database? I have data for Tennis players and each players name is stored in the field ‘name (varchar(60)’ and use a fetch array query to loop through the records and store the fields as arrays e.g.

while($row = mysql_fetch_array($result)){
$tcgname[]= $row['name'];

When a user clicks the download button I want the filename to be the player’s name. Is it possible to do this using the array that stores the name above? If so what change do I need to make to my download script? I have tried things like :

header('Content-Disposition: attachment; filename=($tcgname[$i]).'.png');
<code></code>

With $i being a count of the array (I have omitted the code).

But get syntax errors.

This is my download script :

<?php
$file = trim($_GET['path']);

// force user to download the image
if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: image/png');
    header('Content-Disposition: attachment; filename=tcg_'.rand(100,999).'.png');
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    ob_clean();
    flush();
    readfile($file);
    unlink($file);
    exit;
}
else {
    echo "error not found";
}

?>

[Ilan Firsov]

In the example you have tried you have a missing single-quote'. either fix the concatenation (and missing quote), or change the single-quote to double-quotes and change the brackets to curly brackets {}
either way should work:

    header('Content-Disposition: attachment; filename=' . $tcgname[$i] . '.png'); //the brackets are not required here

or

    header("Content-Disposition: attachment; filename={$tcgname[$i]}.png");

[MBM]

Both pieces of code output a file named png i.e. not extension just png.

[__]

Both pieces of code output a file named png i.e. not extension just png.

Which would indicate that $tcgname[$i] is empty (or is not set). Do you have error reporting enabled? You can inspect the contents of $tcgname and $i using var_dump.

Also,

$file = trim($_GET['path']);

//  . . .

readfile($file);
unlink($file);

You need to validate the contents of $_GET['path'] (e.g., by checking that it names a file in a particular “allowed” directory). Using this script, one may read —and then delete— any file on your computer that is readable by PHP, simply by knowing, or guessing, its name.

[MBM]

Yes error reporting is enabled.

$tcgname[$i]

Displays the value of the name field inside a table cell and all the values in this field can be seen by paginating through the records when displaying and editing records so there’s no issue there. If I add :

var_dump ($tcgname[$i]);

In the download.php script it gives a headers already modified/sent error.

[Ilan Firsov]

Headers already sent warning is perfectly fine here since you are changing headers after your var_dump output (and it is a warning not an error. it does not prevent the rest of the code from executing unless it relies on the new headers)

What is the output of the var_dump? I’d try to var_dump $tcgname and $i as well (sometimes even the $row) just to make sure that they are set correctly, but that’s just me and my debugging techniqe, I like to dump everything that relates to my problem :)

You might want to put an exit; after the var_dump to make sure you only output the var_dump

[__]

If I add : var_dump ($tcgname[$i]); In the download.php script it gives a headers already modified/sent error.

Which is to be expected, since we are interrupting the script to look at the value of that variable. But what is the output of var_dump?

~ ~ ~ ~ ~ ~ ~ ~ ~ ~
After looking back over the code you have posted, I find myself more confused. Is this a single script, or two?

The fact that you say you want something to happen “When a user clicks the download button” implies that you’re dealing with two page requests, as well. If this is the case, you do realize that variables from the first script/request don’t exist in the second…?

Perhaps you should explain the situation here in a little more detail.

[Author]

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