PHP array_values() & array_unique() Functions for Array Manipulation

June 13, 2023

PHP Programming

Arrays are fundamental data structures in PHP that allow developers to store and manipulate multiple values under a single variable. PHP provides a rich set of built-in functions to perform various operations on arrays, making array manipulation efficient and convenient. Two such functions are array_values() and array_unique(). In this article, we will explore these functions and understand how they can be used in combination to manipulate arrays effectively.

PHP array_values() Function

The array_values() function in PHP is a powerful tool that retrieves all the values from an array while discarding their corresponding keys. It creates a new array with sequential integer keys, starting from zero, based on the original array’s values.

The syntax for array_values() is as follows:

array_values(array $array): array

The $array parameter represents the input array from which you want to retrieve the values. The function returns a new array containing only the values.

Example: Using array_values()

Consider the following example:

$fruits = array("apple" => "red", "banana" => "yellow", "orange" => "orange");
$values = array_values($fruits);

print_r($values);

Output:

Array
(
    [0] => red
    [1] => yellow
    [2] => orange
)

In this example, the array_values() function extracts the values from the $fruits array, discards the associative keys, and assigns sequential integer keys to the resulting array. The output displays the values (“red”, “yellow”, “orange”) in the same order as they appeared in the original array.

PHP array_unique() Function

The array_unique() function in PHP is used to remove duplicate values from an array, resulting in a new array with unique values. It preserves the order of the elements while discarding the duplicate occurrences.

The syntax for array_unique() is as follows:

array_unique(array $array, int $sort_flags = SORT_STRING): array

The $array parameter represents the input array from which you want to remove duplicates. The optional $sort_flags parameter allows you to specify the sorting behavior of the resulting array.

Example: Using array_unique()

Consider the following example:

$numbers = array(1, 2, 3, 4, 3, 2, 1);
$uniqueNumbers = array_unique($numbers);

print_r($uniqueNumbers);

Output

Array
(
    [0] => 1
    [1] => 2
    [2] => 3
    [3] => 4
)

In this example, the array_unique() function removes the duplicate values from the $numbers array, resulting in a new array $uniqueNumbers. The output displays the unique values (1, 2, 3, 4) while maintaining their original order.

Combining array_values() and array_unique()

The array_values() and array_unique() functions can be combined to manipulate arrays effectively. By applying array_values() after array_unique(), we can obtain a new array with unique values and sequential integer keys.

Consider the following example:

$colors = array("red", "green", "blue", "green", "yellow");
$uniqueColors = array_unique($colors);
$uniqueValues = array_values($uniqueColors);

print_r($uniqueValues);

Output:

Array
(
    [0] => red
    [1] => green
    [2] => blue
    [3] => yellow
)

In this example, the array_unique() function removes the duplicate values from the $colors array, resulting in $uniqueColors array. Then, array_values() is applied to $uniqueColors to obtain the $uniqueValues array, which has sequential integer keys assigned to the unique values. The output displays the unique values (“red”, “green”, “blue”, “yellow”) with sequential integer keys.

Conclusion

The array_values() and array_unique() functions in PHP are powerful tools for array manipulation. By utilizing array_values(), we can retrieve the values from an array while discarding the keys. On the other hand, array_unique() allows us to remove duplicate values from an array. When combined, these functions enable us to obtain a new array with unique values and sequential integer keys. By understanding and utilizing these functions effectively, PHP developers can manipulate arrays efficiently and perform various array operations with ease.

Note: PHP documentation for additional details and explore other array-related functions available in PHP. Happy coding!

Pradeep Kumar: Node JS, Android, PHP, JAVA, AJAX, ReactJS, IoT
Performance-driven & Result Oriented Software Professional with extensive experience in designing, analysing, developing, delivering and supporting fast paced Web and Mobile Applications..