Class yii\helpers\BaseArrayHelper

Returns the values of a specified column in an array.

The input array should be multidimensional or an array of objects.

For example,

$array = [
    ['id' => '123', 'data' => 'abc'],
    ['id' => '345', 'data' => 'def'],
];
$result = ArrayHelper::getColumn($array, 'id');
// the result is: ['123', '345']

// using anonymous function
$result = ArrayHelper::getColumn($array, function ($element) {
    return $element['id'];
});

Retrieves the value of an array element or object property with the given key or property name.

If the key does not exist in the array or object, the default value will be returned instead.

The key may be specified in a dot format to retrieve the value of a sub-array or the property of an embedded object. In particular, if the key is x.y.z, then the returned value would be $array['x']['y']['z'] or $array->x->y->z (if $array is an object). If $array['x'] or $array->x is neither an array nor an object, the default value will be returned. Note that if the array already has an element x.y.z, then its value will be returned instead of going through the sub-arrays. So it is better to be done specifying an array of key names like ['x', 'y', 'z'].

Below are some usage examples,

// working with array
$username = \yii\helpers\ArrayHelper::getValue($_POST, 'username');
// working with object
$username = \yii\helpers\ArrayHelper::getValue($user, 'username');
// working with anonymous function
$fullName = \yii\helpers\ArrayHelper::getValue($user, function ($user, $defaultValue) {
    return $user->firstName . ' ' . $user->lastName;
});
// using dot format to retrieve the property of embedded object
$street = \yii\helpers\ArrayHelper::getValue($users, 'address.street');
// using an array of keys to retrieve the value
$value = \yii\helpers\ArrayHelper::getValue($versions, ['1.0', 'date']);

Decodes HTML entities into the corresponding characters in an array of strings.

Only array values will be decoded by default. If a value is an array, this method will also decode it recursively. Only string values will be decoded.

See also http://www.php.net/manual/en/function.htmlspecialchars-decode.php.

Encodes special characters in an array of strings into HTML entities.

Only array values will be encoded by default. If a value is an array, this method will also encode it recursively. Only string values will be encoded.

See also http://www.php.net/manual/en/function.htmlspecialchars.php.

Indexes an array according to a specified key.

The input array should be multidimensional or an array of objects.

The key can be a key name of the sub-array, a property name of object, or an anonymous function which returns the key value given an array element.

If a key value is null, the corresponding array element will be discarded and not put in the result.

For example,

$array = [
    ['id' => '123', 'data' => 'abc'],
    ['id' => '345', 'data' => 'def'],
];
$result = ArrayHelper::index($array, 'id');
// the result is:
// [
//     '123' => ['id' => '123', 'data' => 'abc'],
//     '345' => ['id' => '345', 'data' => 'def'],
// ]

// using anonymous function
$result = ArrayHelper::index($array, function ($element) {
    return $element['id'];
});

Returns a value indicating whether the given array is an associative array.

An array is associative if all its keys are strings. If $allStrings is false, then an array will be treated as associative if at least one of its keys is a string.

Note that an empty array will NOT be considered associative.

Returns a value indicating whether the given array is an indexed array.

An array is indexed if all its keys are integers. If $consecutive is true, then the array keys must be a consecutive sequence starting from 0.

Note that an empty array will be considered indexed.

Checks if the given array contains the specified key.

This method enhances the array_key_exists() function by supporting case-insensitive key comparison.

Builds a map (key-value pairs) from a multidimensional array or an array of objects.

The $from and $to parameters specify the key names or property names to set up the map. Optionally, one can further group the map according to a grouping field $group.

For example,

$array = [
    ['id' => '123', 'name' => 'aaa', 'class' => 'x'],
    ['id' => '124', 'name' => 'bbb', 'class' => 'x'],
    ['id' => '345', 'name' => 'ccc', 'class' => 'y'],
];

$result = ArrayHelper::map($array, 'id', 'name');
// the result is:
// [
//     '123' => 'aaa',
//     '124' => 'bbb',
//     '345' => 'ccc',
// ]

$result = ArrayHelper::map($array, 'id', 'name', 'class');
// the result is:
// [
//     'x' => [
//         '123' => 'aaa',
//         '124' => 'bbb',
//     ],
//     'y' => [
//         '345' => 'ccc',
//     ],
// ]

Merges two or more arrays into one recursively.

If each array has an element with the same string key value, the latter will overwrite the former (different from array_merge_recursive). Recursive merging will be conducted if both arrays have an element of array type and are having the same key. For integer-keyed elements, the elements from the latter array will be appended to the former array.

Sorts an array of objects or arrays (with the same structure) by one or several keys.

Removes an item from an array and returns the value. If the key does not exist in the array, the default value will be returned instead.

Usage examples,

// $array = ['type' => 'A', 'options' => [1, 2]];
// working with array
$type = \yii\helpers\ArrayHelper::remove($array, 'type');
// $array content
// $array = ['options' => [1, 2]];

Converts an object or an array of objects into an array.