PHP Remove From Array - How to Remove Elements from Arrays in PHP

Managing arrays effectively is crucial for any PHP developer, and one common task is removing elements from an array. In this blog post, we’ll explore various methods to remove items from arrays in PHP, covering different types of arrays and removal techniques.

Removing Elements by Value

Example 1: Using unset

The unset function can be used to remove an element by its key.

$fruits = ['apple', 'banana', 'cherry', 'date'];
unset($fruits[1]); // Removes 'banana'
print_r($fruits);

Output:

Array
(
    [0] => apple
    [2] => cherry
    [3] => date
)

Note that unset does not reindex the array. To reindex, use array_values.

$fruits = array_values($fruits);
print_r($fruits);

Output:

Array
(
    [0] => apple
    [1] => cherry
    [2] => date
)

Example 2: Using array_diff

To remove an element by value, array_diff is handy.

$fruits = ['apple', 'banana', 'cherry', 'date'];
$fruits = array_diff($fruits, ['banana']);
print_r($fruits);

Output:

Array
(
    [0] => apple
    [2] => cherry
    [3] => date
)

Removing Elements by Key

Example 3: Using array_splice

array_splice can be used to remove elements by key and reindex the array.

$fruits = ['apple', 'banana', 'cherry', 'date'];
array_splice($fruits, 1, 1); // Removes 'banana'
print_r($fruits);

Output:

Array
(
    [0] => apple
    [1] => cherry
    [2] => date
)

Removing Elements from Associative Arrays

Example 4: Using unset

For associative arrays, unset is straightforward.

$person = ['name' => 'John', 'age' => 30, 'city' => 'New York'];
unset($person['age']); // Removes 'age'
print_r($person);

Output:

Array
(
    [name] => John
    [city] => New York
)

Example 5: Using array_filter

To remove elements based on a condition, use array_filter.

$person = ['name' => 'John', 'age' => 30, 'city' => 'New York'];
$person = array_filter($person, function($key) {
    return $key !== 'age';
}, ARRAY_FILTER_USE_KEY);
print_r($person);

Output:

Array
(
    [name] => John
    [city] => New York
)

Removing Duplicate Elements

Example 6: Using array_unique

To remove duplicates from an array, use array_unique.

$numbers = [1, 2, 2, 3, 4, 4, 5];
$unique_numbers = array_unique($numbers);
print_r($unique_numbers);

Output:

Array
(
    [0] => 1
    [1] => 2
    [3] => 3
    [4] => 4
    [6] => 5
)

Removing Elements Based on Condition

Example 7: Using array_filter

To remove elements based on a custom condition, array_filter is versatile.

$numbers = [1, 2, 3, 4, 5, 6];
$even_numbers = array_filter($numbers, function($number) {
    return $number % 2 !== 0; // Keep odd numbers
});
print_r($even_numbers);

Output:

Array
(
    [0] => 1
    [2] => 3
    [4] => 5
)

Conclusion

PHP provides multiple ways to remove elements from arrays, whether you’re dealing with indexed arrays, associative arrays, or arrays with duplicate values. By understanding and utilizing functions like unset, array_diff, array_splice, array_filter, and array_unique, you can manage your arrays more effectively and write cleaner, more efficient code.

Experiment with these techniques in your projects to find the most suitable methods for your specific use cases.