File Download Security 

This script prevents the file to be linking to other file as this script force the file to be downloaded well before the beginning of downloads. This script is very crucial for highly secured documents. 

In this script, filter_var() is used for filtering the file and valid string  validating the file that filters the file using FILTER_SANITIZE_STRING into downloadable file. 

Initialize with PHP tag (<?php), use filter_var() to filter the downloadable file and validate that file from array (mytextfile.txt), print the output of the script with die command. End the PHP tag. See the example:

<?php
// filter
$myFile = filter_var($_GET['file'], FILTER_SANITIZE_STRING);

// Then validate
$valid = array('mytextfile.txt', 'mytextfile.txt');
If (!in_array($myFile, $valid)) {
die('H; This is for validation');
}

include($myFile);

?>
 

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