Renaming certain files after upload.

[cjason]

Hi all, i've got a script that i've part edited to accept only certain file types to be uploaded, eg; JPG, PNG, JPEG etc. the script is originally part of the "uploadify script", im new to php so im finding it hard to work out how i can add a function to rename files on the backend so i dont get duplicates or errors on upload, but keep original names for the frontend. if this all makes sense, thanks in advance - Cody

<?php

if (!empty($_FILES)) {
	$tempFile = $_FILES['Filedata']['tmp_name'];
	$targetPath = $_SERVER['DOCUMENT_ROOT'] . $_REQUEST['folder'] . '/';
	$targetFile =  str_replace('//','/',$targetPath) . $_FILES['Filedata']['name'];
	
	
	$fileTypes = array('jpg','jpeg','gif','png'); // File extensions
	$fileParts = pathinfo($_FILES['Filedata']['name']);
	
	if (in_array($fileParts['extension'],$fileTypes)) {
		move_uploaded_file($tempFile,$targetFile);
		echo '1';
	} else {
		echo 'Invalid file type.';
	}
}
?>

[Fou-Lu]

No that doesn't really make any sense. What is the difference between the front and back end when it comes to this code? The user can upload any file they want, you can rename it to anything you want.
To rename, simply modify $targetFile to change what you need. The problem I see overall is on conflict even with a conflict detection and correction, how will you determine which of the conflicted files is the same as this file just uploaded at a later time?
You'd be better off using a database to associate random generated file names to the user uploading them (or whatever you plan on using for an association). Then you can display whatever you want within the database and the file names themselves have no impact on the display.