Creates a callable function and parameter list from a string representation. Note that this function does not validate the callback string.

// Get the callback function and parameters
list($func, $params) = Arr::callback('Foo::bar(apple,orange)');

// Get the result of the callback
$result = call_user_func_array($func, $params);

Retrieves multiple keys from an array. If the key does not exist in the array, the default value will be added instead.

// Get the values "username", "password" from $_POST
$auth = Arr::extract($_POST, array('username', 'password'));

Convert a multi-dimensional array into a single-dimensional array.

$array = array('set' => array('one' => 'something'), 'two' => 'other');

// Flatten the array
$array = Arr::flatten($array);

// The array will now be
array('one' => 'something', 'two' => 'other');

The keys of array values will be discarded.

Retrieve a single key from an array. If the key does not exist in the array, the default value will be returned instead.

// Get the value "username" from $_POST, if it exists
$username = Arr::get($_POST, 'username');

// Get the value "sorting" from $_GET, if it exists
$sorting = Arr::get($_GET, 'sorting');

Test if a value is an array with an additional check for array-like objects.

// Returns TRUE
Arr::is_array(array());
Arr::is_array(new ArrayObject);

// Returns FALSE
Arr::is_array(FALSE);
Arr::is_array('not an array!');
Arr::is_array(Database::instance());

Tests if an array is associative or not.

// Returns TRUE
Arr::is_assoc(array('username' => 'john.doe'));

// Returns FALSE
Arr::is_assoc('foo', 'bar');

Recursive version of array_map, applies one or more callbacks to all elements in an array, including sub-arrays.

// Apply "strip_tags" to every element in the array
$array = Arr::map('strip_tags', $array);

// Apply $this->filter to every element in the array
$array = Arr::map(array(array($this,'filter')), $array);

// Apply strip_tags and $this->filter to every element
$array = Arr::map(array('strip_tags',array($this,'filter')), $array);

Because you can pass an array of callbacks, if you wish to use an array-form callback you must nest it in an additional array as above. Calling Arr::map(array($this,'filter'), $array) will cause an error. [!!] Unlike array_map, this method requires a callback and will only map a single array.

Merges one or more arrays recursively and preserves all keys. Note that this does not work the same as array_merge_recursive!

$john = array('name' => 'john', 'children' => array('fred', 'paul', 'sally', 'jane'));
$mary = array('name' => 'mary', 'children' => array('jane'));

// John and Mary are married, merge them together
$john = Arr::merge($john, $mary);

// The output of $john will now be:
array('name' => 'mary', 'children' => array('fred', 'paul', 'sally', 'jane'))

Overwrites an array with values from input arrays. Keys that do not exist in the first array will not be added!

$a1 = array('name' => 'john', 'mood' => 'happy', 'food' => 'bacon');
$a2 = array('name' => 'jack', 'food' => 'tacos', 'drink' => 'beer');

// Overwrite the values of $a1 with $a2
$array = Arr::overwrite($a1, $a2);

// The output of $array will now be:
array('name' => 'jack', 'mood' => 'happy', 'food' => 'tacos')

Gets a value from an array using a dot separated path.

// Get the value of $array['foo']['bar']
$value = Arr::path($array, 'foo.bar');

Using a wildcard "*" will search intermediate arrays and return an array.

// Get the values of "color" in theme
$colors = Arr::path($array, 'theme.*.color');

// Using an array of keys
$colors = Arr::path($array, array('theme', '*', 'color'));

Retrieves muliple single-key values from a list of arrays.

// Get all of the "id" values from a result
$ids = Arr::pluck($result, 'id');

A list of arrays is an array that contains arrays, eg: array(array $a, array $b, array $c, ...)

Fill an array with a range of numbers.

// Fill an array with values 5, 10, 15, 20
$values = Arr::range(5, 20);

Set a value on an array by path.

Adds a value to the beginning of an associative array.

// Add an empty value to the start of a select list
Arr::unshift($array, 'none', 'Select a value');