PHP array_shift: Remove the First Element of an Array

This article provides a quick guide on how to use the array_shift() function in PHP to remove and return the first element of an array. You will learn the syntax, see a practical code example, and understand how the function modifies array keys and handles empty inputs.

The array_shift() function shifts the first value of the array off and returns it, shortening the array by one element.

Syntax of array_shift()

array_shift(array &$array): mixed

$array: The input array. This array is passed by reference, meaning the function directly modifies the original variable.
Return Value: Returns the removed value, or null if the array is empty.

Code Example

Here is a straightforward example demonstrating how to remove the first element and assign it to a variable:

<?php
$fruits = ["apple", "banana", "cherry"];

// Remove and return the first element
$first_fruit = array_shift($fruits);

// Output the removed element
echo "Removed Element: " . $first_fruit . "\n"; 
// Output: Removed Element: apple

// Output the modified array
print_r($fruits);
/*
Output:
Array
(
    [0] => banana
    [1] => cherry
)
*/
?>

Key Behaviors of array_shift()

Direct Modification: Because array_shift() takes the array by reference, the original array is modified directly. You do not need to reassign the function output back to the array.
Key Reindexing: Numerical keys in the array are automatically reindexed starting from zero. Literal (string) keys, however, are preserved and remain unchanged.
Handling Empty Arrays: If you pass an empty array to array_shift(), the function will return null without throwing an error.