Reading File Directories : Repeating Functions

Functions are a very important part of resuable code.

Retrieve Directory Listing

This function reads all of the files and subdirectories in a given folder, and returns a multi-dimensional array containing all the information.

Each subdirectory is stored as a new layer.

<?php
function retrieveDirs($rootdirpath) {
	$array = false;
	if ($dir = @opendir($rootdirpath)) {
while ($file = readdir($dir)) {
	if (is_dir($rootdirpath."/".$file) && $file != "." && $file != "..") {
		$array [$rootdirpath."/".$file]
			= retrieveDirs($rootdirpath."/".$file);
	} elseif($file != "." && $file != "..") {
		$array [] = $rootdirpath."/".$file;
	}
}
		closedir($dir);
	}
	return $array;
}
?>

A quick run through of how it works.

If the supplied directory can be opened read each file from the directory.

If the file, is a directory, run the same function again, but on the new directory.

If the file isn't a directory, and isn't "." or ".." (special directory browsing things) then add the file path into the array as an entry.

Returned from the function is an array containing the list of files in the directory.

Arrays can be stored within arrays. Sub folders are entered as arrays within arrays containing the list of files.

Note: The full path of the file is stored, not just the file name. Hence $rootdirpath."/".$file.

Using the array

Okay, thats great.. you can now read a whole directory tree into an array. How do you make use of this information? Lets display it on screen.

<?php
function echoArray($array, $level=1) {
	foreach($array as $key=>$value) {
		if(is_array($value)) {
			echo "<h$level>$key</h$level>";
			echoArray($value, $level+1);
		} else {
			echo "<h$level>$key : $value</h$level>";
		}
	}
}
?>

This repeating function echos each value in an array. If an entry is an array, then it goes into a sub-loop to echo that array.
I added a $level variable, so that you can easily see how the array is stacked when its outputted.

Test the script

You can try this script out. Put it in the base of your web directory, include the two functions above.

<?php
	// Include Directory and Array functions.
include("functions.php");

	// Create array of files/sub-directories
$array = retrieveDirs('..');
	// Echo array
echoArray($array);
?>

Closing words

Reading files from directories is dead simple. Just remember to close the directory after you've finished (can sometimes cause problems if you don't).

Feel free to use the functions I made. They're quick to make and very useful. When you learn how to upload files to servers, you'll realise how important it is to manage files. Many websites already offer PHP based file management systems, but nothing beats being able to make your own.

Author: Markavian
Last edited on: 22nd Jan, 9:14 am
Please rate this article.

« Prev page 'Useful Filters' «

tutorial Pages

Introduction
Useful functions
Read and Output
Useful Filters
Repeating Functions