In this article, we will see how to get specific key values from the given array. PHP array is a collection of items that are stored under keys. There are two possible types of keys: strings and integers. For any type of key, there is a common syntax to get a specific value by key — square brackets.
Example 1:
PHP
<?php   $mixedArr = [     10,     20,     'hello' => 'world',     30, ];   // Get a specific value by index $firstItem = $mixedArr[0]; echo "An item by index 0: {$firstItem}\n";   // Get a specific value by string key $stringItem = $mixedArr['hello']; echo "An item by key 'hello': {$stringItem}\n";   ?> |
Output
An item by index 0: 10 An item by key 'hello': world
Example 2: Sometimes we can accidentally try to get a non-existent item from the array. In this case, PHP throws a NOTICE. To avoid the issue, we have to check the key existence before accessing it.Â
PHP
<?php   $arr = [1, 2, 3];   // Check the key existence with // the built-in 'isset' function if (isset($arr[10])) {     echo "index 10 value is: {$arr[10]}\n"; } else {     echo "There are no value under the index 10\n"; }   $value = $arr[10] ?? 'unknown';   echo "A value under the index 10: {$value}\n";   ?> |
Output
There are no value under the index 10 A value under the index 10: unknown
