Set your Publisher ID in src/config/ads.ts to display live ads.
Indexed, Associative & Multidimensional Arrays
Mastering PHP dictionary mappings and array transformation pipelines
An array in PHP is actually an ordered map—a data type that associates values to keys. This allows PHP arrays to function as lists, hash maps, queues, and multidimensional matrices seamlessly.
Working with Arrays in PHP
Indexed arrays use numeric indices starting at 0: $colors = ["red", "green", "blue"];.
Associative arrays use named keys: $user = ["name" => "Sarah", "role" => "Admin"];.
The foreach loop provides clean iteration over both keys and values: foreach ($map as $key => $val).
PHP includes hundreds of built-in array functions such as array_map(), array_filter(), array_merge(), and in_array().
<?php
$products = [
["id" => 101, "name" => "Mechanical Keyboard", "price" => 129.99, "stock" => 14],
["id" => 102, "name" => "Ergonomic Mouse", "price" => 59.99, "stock" => 0],
["id" => 103, "name" => "4K Monitor 27\"", "price" => 349.00, "stock" => 8],
];
// Filter in-stock items
$inStock = array_filter($products, function($p) {
return $p["stock"] > 0;
});
// Calculate total inventory value
$totalVal = array_reduce($inStock, function($acc, $p) {
return $acc + ($p["price"] * $p["stock"]);
}, 0);
echo "Available inventory value: $" . number_format($totalVal, 2);
?>Set your Publisher ID in src/config/ads.ts to display live ads.
Test Yourself With Exercise
Which syntax defines an associative array pairing in PHP?