In this tutorial, you shall learn how to reverse an array in PHP using array_reverse() function, with syntax and examples.
PHP Reverse Array
To reverse an array in PHP, we can use array_reverse() function.
The PHP array_reverse() function returns a new array with elements of the original array in reverse order.
In this tutorial, we will learn how to use array_reverse() function to reverse the order of elements in given array.
Syntax
The syntax of array_reverse() function is
array_reverse( array, preserve )
where
Parameter | Description |
---|---|
array | [mandatory] The source array for reversing. |
preserve | [optional] Boolean value telling if the function should preserve the keys of the indexed array or not. This parameter has no effect on associative arrays. |
Function Return Value
array_reverse() returns the a new array with elements of the source array arranged in reverse order. Original array/ Source array remains unchanged.
Examples
1. Reverse an Indexed Array
In this example, we will take an indexed array of items, and reverse the order of elements using array_reverse() function.
PHP Program
<?php $array1 = array(5=>"apple", "banana", "mango"); $result = array_reverse($array1); print_r($result); ?>
Output
With default value of preserve parameter being FALSE, the indexes for the items are not preserved in the resulting reverse array.
![PHP array_reverse() - Reverse an Indexed Array](https://www.tutorialkart.com/wp-content/uploads/2020/11/image-18.png)
2. Reverse an Associative Array
In this example, we will take an array of items, say array1, and create a new array with elements of array1 but in reverse order.
PHP Program
<?php $array1 = array("a"=>"apple", "b"=>"banana", "m"=>"mango"); $result = array_reverse($array1); print_r($result); ?>
Output
![PHP array_reverse() - Reverse an Array](https://www.tutorialkart.com/wp-content/uploads/2020/11/image-17.png)
3. Preserve the original indices while reversing indexed array
In this example, we will try with argument value of TRUE for preserve parameter when calling array_reverse()
function.
PHP Program
<?php $array1 = array(5=>"apple", "banana", "mango"); $result = array_reverse($array1, TRUE); print_r($result); ?>
Output
The index of the items in the reversed array should have the indexes from the same array.
![PHP array_reverse() - preserve=TRUE for Indexed Arrays](https://www.tutorialkart.com/wp-content/uploads/2020/11/image-19.png)
Conclusion
In this PHP Tutorial, we learned how to reverse an array, using PHP Array array_reverse() function.