Restructure multidimensional array based on associative array key - php

Question

I have the following array:
$products = [
[
'id' => 21,
'name' => 'Floral Dress',
'params' => [
'size' => 14,
'price' => 23.99,
'department' => 'Dresses'
]
],
[
'id' => 413,
'name' => 'Maxi Skirt',
'params' => [
'size' => 10,
'price' => 12.99,
'department' => 'Skirts'
]
],
[
'id' => 78,
'name' => 'A Line Prom Dress',
'params' => [
'size' => 10,
'price' => 79.99,
'department' => 'Dresses'
]
],
[
'id' => 212,
'name' => 'Nude Block High Heels',
'params' => [
'size' => 6,
'price' => 20.99,
'department' => 'Shoes'
]
],
[
'id' => 54,
'name' => 'Denim Trim Dress',
'params' => [
'size' => 8,
'price' => 52.99,
'department' => 'Dresses'
]
],
];
Unfortunately I cannot control how the array is built.
Instead I need to restructure the data so that the array is sorted by the ['params']['department'] key.
So ideally I would take the above and output it like so:
$products = [
'Dresses' => [
[
'id' => 21,
'name' => 'Floral Dress',
'params' => [
'size' => 14,
'price' => 23.99
]
],
[
'id' => 78,
'name' => 'A Line Prom Dress',
'params' => [
'size' => 10,
'price' => 79.99
]
],
[
'id' => 54,
'name' => 'Denim Trim Dress',
'params' => [
'size' => 8,
'price' => 52.99
]
],
],
'Skirts' => [
[
'id' => 413,
'name' => 'Maxi Skirt',
'params' => [
'size' => 10,
'price' => 12.99
]
],
],
'Shoes' => [
[
'id' => 212,
'name' => 'Nude Block High Heels',
'params' => [
'size' => 6,
'price' => 20.99
]
],
]

Answer 1

You could simply iterate over all the products and populate a new associative array holding the departments, which are themselves arrays of corresponding products. See the comments in the code below.
<?php
// same data as in the question, just in one line for better overview
$products = [['id' => 21,'name' => 'Floral Dress','params' => ['size' => 14,'price' => 23.99,'department' => 'Dresses']],['id' => 413,'name' => 'Maxi Skirt','params' => ['size' => 10,'price' => 12.99,'department' => 'Skirts']],['id' => 78,'name' => 'A Line Prom Dress','params' => ['size' => 10,'price' => 79.99,'department' => 'Dresses']],['id' => 212,'name' => 'Nude Block High Heels','params' => ['size' => 6,'price' => 20.99,'department' => 'Shoes']],['id' => 54,'name' => 'Denim Trim Dress','params' => ['size' => 8,'price' => 52.99,'department' => 'Dresses']]];
// initialize empty department array
$departments = array();
// iterate over all the products
foreach ( $products as $product ) {
// get this product's department
$product_department = $product['params']['department'];
// unset the department in the params array
unset( $product['params']['department'] );
// initialize this department as an empty array
// if it doesn't exist yet
if ( !isset( $departments[$product_department] ) ) {
$departments[$product_department] = array();
}
// push this product in its corresponding department
$departments[$product_department][] = $product;
}
var_dump( $departments );

Answer 2

$groupedProducts = [];
foreach ($products as &$product) {
$department = $product['params']['department'];
unset($product['params']['department']);
$groupedProducts[$department] = $product;
}
var_dump($groupedProducts);