PHP Associative Arrays

Associative arrays use named keys instead of numeric positions. This makes the data easier to read and access by meaning.

Creating an associative array

Use the key => value syntax.

<?php
$person = [
    "name" => "Carla",
    "age" => 28,
    "city" => "Lisbon"
];

Accessing values

Use the key inside square brackets.

<?php
echo $person["name"]; // Carla
echo $person["age"];  // 28

Adding or changing values

<?php
$person["email"] = "carla@example.com"; // add
$person["age"] = 29;                      // update

Looping with foreach

foreach can read both the key and the value.

<?php
foreach ($person as $key => $value) {
    echo "$key: $value\n";
}
// name: Carla
// age: 29
// city: Lisbon

Checking a key

Use isset() to verify a key exists before using it.

<?php
if (isset($person["name"])) {
    echo "Name is set";
}