Compressing a file (zip) with a password in PHP

Bonjour chers tous !

I have a version of PHP 5.6.3
I want to create a zip with a password via a PHP script.
With the function below I can compress my files but the password is not requested during decompression. (Password doesn't work)

Can someone help me?

Here is my script:

<?php
//**********function to compress files into zip********

function createZipFile($zipfile,$files){

$zip=new ZipArchive();

if($zip->open($zipfile, ZipArchive::CREATE) !== TRUE){

throw new Exception('Error: unable to open or create');

}

foreach($files as $file){

$zip->addFile($file);

$zip->setPassword('Password2');

}

$zip->close();

}

?>