Arrays
PHP 8.2 • Data Storage and Manipulation
Introduction to Arrays
Arrays are ordered maps that can hold scalar values or reference other arrays. PHP supports indexed and associative arrays.
Indexed Arrays
1. Numerical Indexing
<?php
$fruits = ['apple', 'banana', 'cherry'];
foreach ($fruits as $fruit) {
echo $fruit . "
";
}
?>
Access elements via numeric keys starting from zero.
2. Multi-Dimensional Arrays
<?php
$matrix = [
[1, 2, 3],
[4, 5, 6],
[7, 8, 9]
];
print_r($matrix);
?>
Nested arrays can represent matrices or complex data structures.
Associative Arrays
Key-Value Pairs
<?php
$prices = [
'apple' => 1.50,
'banana' => 0.75,
'cherry' => 2.00
];
echo 'Apple price: $' . $prices['apple'];
?>
Use custom strings as keys for more readable data structures.
Array Functions
1. Built-in Array Tools
<?php $numbers = [3, 1, 4, 1, 5, 9]; sort($numbers); print_r($numbers); ?>
2. Array Iteration
<?php $users = ['Alice', 'Bob', 'Charlie']; array_map(fn($user) => 'Hello, ' . $user, $users); ?>
Best Practices
Use Type Checks
Verify data types using is_array() when handling user input.
Optimize Memory
Leverage foreach for readability and performance with big arrays.
See Also
Tip: Prefer foreach for array iteration. Use array_map or other functional functions for complex transformations.