How do I create a multidimensional tree array from a flat array? - php

Question

'I have this flat array:
$folders = [
'test/something.txt',
'test/hello.txt',
'test/another-folder/myfile.txt',
'test/another-folder/kamil.txt',
'test/another-folder/john/hi.txt'
]
And I need it in the following format:
$folders = [
'test' => [
'something.txt',
'hello.txt',
'another-folder' => [
'myfile.txt',
'kamil.txt',
'john' => [
'hi.txt'
]
]
]
];
How do I do this? Thanks.

Answer 1

Recursion is your friend :-)
function createArray($folders, $output){
if(count($folders) > 2){
$key = array_shift($folders);
$output[$key] = createArray(
$folders, isset($output[$key]) ? $output[$key] : []
);
}
else{
if(!isset($output[$folders[0]])){
$output[$folders[0]] = [];
}
$output[$folders[0]][] = $folders[1];
}
return $output;
}
Keep drilling down until you get to the file name, then add them all together in an array.
You need to call this function for each element in your array, like this:
$newFolders = [];
foreach($folders as $folder){
$newFolders = createArray(explode('/', $folder), $newFolders);
}
DEMO: https://eval.in/139240

Answer 2

<?php
$folders = [
'test/something.txt',
'test/hello.txt',
'test/another-folder/myfile.txt',
'test/another-folder/kamil.txt',
'test/another-folder/john/hi.txt'
];
$new_folders = array();
foreach ($folders as $folder) {
$reference =& $new_folders;
$parts = explode('/', $folder);
$file = array_pop($parts);
foreach ($parts as $part) {
if(!isset($reference[$part])) {
$reference[$part] = [];
}
$reference =& $reference[$part];
}
$reference[] = $file;
}
var_dump($new_folders);