PHP: How to Remove Specific Element from an Array

PHP: How to remove specific element from an array?

Use array_search to get the key and remove it with unset if found:

if (($key = array_search('strawberry', $array)) !== false) {
    unset($array[$key]);
}

array_search returns false (null until PHP 4.2.0) if no item has been found.

And if there can be multiple items with the same value, you can use array_keys to get the keys to all items:

foreach (array_keys($array, 'strawberry') as $key) {
    unset($array[$key]);
}

Deleting an element from an array in PHP

There are different ways to delete an array element, where some are more useful for some specific tasks than others.

Deleting a single array element

If you want to delete just one array element you can use unset() or alternatively \array_splice().

If you know the value and don’t know the key to delete the element you can use \array_search() to get the key. This only works if the element does not occur more than once, since \array_search returns the first hit only.

unset()

Note that when you use unset() the array keys won’t change. If you want to reindex the keys you can use \array_values() after unset(), which will convert all keys to numerically enumerated keys starting from 0.

Code:

$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
          // ↑ Key which you want to delete

Output:

[
    [0] => a
    [2] => c
]

\array_splice() method

If you use \array_splice() the keys will automatically be reindexed, but the associative keys won’t change — as opposed to \array_values(), which will convert all keys to numerical keys.

\array_splice() needs the offset, not the key, as the second parameter.

Code:

$array = [0 => "a", 1 => "b", 2 => "c"];
\array_splice($array, 1, 1);
                   // ↑ Offset which you want to delete

Output:

[
    [0] => a
    [1] => c
]

array_splice(), same as unset(), take the array by reference. You don’t assign the return values of those functions back to the array.

Deleting multiple array elements

If you want to delete multiple array elements and don’t want to call unset() or \array_splice() multiple times you can use the functions \array_diff() or \array_diff_key() depending on whether you know the values or the keys of the elements which you want to delete.

\array_diff() method

If you know the values of the array elements which you want to delete, then you can use \array_diff(). As before with unset() it won’t change the keys of the array.

Code:

$array = [0 => "a", 1 => "b", 2 => "c", 3 => "c"];
$array = \array_diff($array, ["a", "c"]);
                          // └────────┘
                          // Array values which you want to delete

Output:

[
    [1] => b
]

\array_diff_key() method

If you know the keys of the elements which you want to delete, then you want to use \array_diff_key(). You have to make sure you pass the keys as keys in the second parameter and not as values. Keys won’t reindex.

Code:

$array = [0 => "a", 1 => "b", 2 => "c"];
$array = \array_diff_key($array, [0 => "xy", "2" => "xy"]);
                               // ↑           ↑
                               // Array keys which you want to delete

Output:

[
    [1] => b
]

If you want to use unset() or \array_splice() to delete multiple elements with the same value you can use \array_keys() to get all the keys for a specific value and then delete all elements.

\array_filter() method

If you want to delete all elements with a specific value in the array you can use \array_filter().

Code:

$array = [0 => "a", 1 => "b", 2 => "c"];
$array = \array_filter($array, static function ($element) {
    return $element !== "b";
    //                   ↑
    // Array value which you want to delete
});

Output:

[
    [0] => a
    [1] => c
]

PHP remove specific item from array

With array_search you can get the first matching key of the given value, then you can delete it with unset.

if (false !== $key = array_search(401, $array)) {
  unset($array[$key]);
}

PHP array delete by value (not key)

Using array_search() and unset, try the following:

if (($key = array_search($del_val, $messages)) !== false) {
    unset($messages[$key]);
}

array_search() returns the key of the element it finds, which can be used to remove that element from the original array using unset(). It will return FALSE on failure, however it can return a false-y value on success (your key may be 0 for example), which is why the strict comparison !== operator is used.

The if() statement will check whether array_search() returned a value, and will only perform an action if it did.

Remove a element from an array and assign to a variable

You can copy the array to $cars_without_volvo and unset from that, then you'd have two different arrays. unset() doesn't return anything, it's used to unset elements or variables directly.

This of course assumes that Volvo is always the first element in the $cars array, because we unset the first element.

$cars = array("Volvo", "BMW", "Toyota");
$cars_without_volvo = $cars;
unset($cars_without_volvo[0]);

print_r($cars);
print_r($cars_without_volvo);

Outputs

Array (
    [0] => Volvo
    [1] => BMW
    [2] => Toyota
)
Array (
    [1] => BMW
    [2] => Toyota
)

You can also find the key for the Volvo element dynamically, by using array_search() (demo), by replacing the unset() line above with the one below.

unset($cars_without_volvo[array_search("Volvo", $cars_without_volvo)]);

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Using array_shift() as shown in the other answer is most likely the better approach - if the element you wish to remove is the first one. If you want to remove elements in a difference index than the first or last, using this approach might be easier.

• PHP.net on unset()
• Live demo

How to remove a single element from a PHP session array?

The easiest way is to get the value, remove the item, and set the session variable again.

$data = $_SESSION['array'];    // Get the value
unset($data[1]);               // Remove an item (hardcoded the second here)
$_SESSION['array'] = $data;    // Set the session value with the new array

Update:

Or like @Qirel said, you can unset the item directly if you know the number.

unset($_SESSION['array'][1]);

Update 2

If you want to remove the element by its value, you can use array_search to find the key of this element. Note that if there are to elements with this value, only the first will be removed.

$value_to_delete = '13/02/2017';
if (($key = array_search($value_to_delete, $_SESSION['array'])) !== false)
    unset($_SESSION['array'][$key]);

How to remove an element in array containing a certain word in PHP

Arrays have keys and values. You're looking at the values, but trying to unset keys. Unless they match (i.e. your array looks like ['test' => 'test', 'freedom' => 'freedom']), this isn't what you want. Try this:

foreach ($myarray as $key => $value){ 
    // remove words containing 'free' 
    if (strpos($value, 'free') !== false) {
        unset($myarray[$key]);
    }
}

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