BaseArrayHelper

API reference › yii › helpers › BaseArrayHelper

class	`yii\helpers\BaseArrayHelper`
Since	2.0
Source	`framework/helpers/BaseArrayHelper.php`

1 subclass

ArrayHelper

BaseArrayHelper provides concrete implementation for ArrayHelper.

Do not use BaseArrayHelper. Use ArrayHelper instead.

Methods

Method	Description	Defined by
`filter()` static	Filters array according to rules specified.	`BaseArrayHelper`
`flatten()` static	Flattens a multidimensional array into a one-dimensional array.	`BaseArrayHelper`
`getColumn()` static	Returns the values of a specified column in an array.	`BaseArrayHelper`
`getValue()` static	Retrieves the value of an array element or object property with the given key or property name.	`BaseArrayHelper`
`htmlDecode()` static	Decodes HTML entities into the corresponding characters in an array of strings.	`BaseArrayHelper`
`htmlEncode()` static	Encodes special characters in an array of strings into HTML entities.	`BaseArrayHelper`
`index()` static	Indexes and/or groups the array according to a specified key.	`BaseArrayHelper`
`isAssociative()` static	Returns a value indicating whether the given array is an associative array.	`BaseArrayHelper`
`isIn()` static	Check whether an array or `Traversable` contains an element.	`BaseArrayHelper`
`isIndexed()` static	Returns a value indicating whether the given array is an indexed array.	`BaseArrayHelper`
`isSubset()` static	Checks whether an array or `Traversable` is a subset of another array or `Traversable`.	`BaseArrayHelper`
`isTraversable()` static	Checks whether a variable is an array or `Traversable`.	`BaseArrayHelper`
`keyExists()` static	Checks if the given array contains the specified key.	`BaseArrayHelper`
`map()` static	Builds a map (key-value pairs) from a multidimensional array or an array of objects.	`BaseArrayHelper`
`merge()` static	Merges two or more arrays into one recursively.	`BaseArrayHelper`
`multisort()` static	Sorts an array of objects or arrays (with the same structure) by one or several keys.	`BaseArrayHelper`
`recursiveSort()` static	Sorts array recursively.	`BaseArrayHelper`
`remove()` static	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.	`BaseArrayHelper`
`removeValue()` static	Removes items with matching values from the array and returns the removed items.	`BaseArrayHelper`
`setValue()` static	Writes a value into an associative array at the key path specified.	`BaseArrayHelper`
`toArray()` static	Converts an object or an array of objects into an array.	`BaseArrayHelper`

Method details

filter()

public static function filter(array $array, iterable $filters): array

Filters array according to rules specified.

For example:

$array = [
    'A' => [1, 2],
    'B' => [
        'C' => 1,
        'D' => 2,
    ],
    'E' => 1,
];

$result = \yii\helpers\ArrayHelper::filter($array, ['A']);
// $result will be:
// [
//     'A' => [1, 2],
// ]

$result = \yii\helpers\ArrayHelper::filter($array, ['A', 'B.C']);
// $result will be:
// [
//     'A' => [1, 2],
//     'B' => ['C' => 1],
// ]

$result = \yii\helpers\ArrayHelper::filter($array, ['B', '!B.C']);
// $result will be:
// [
//     'B' => ['D' => 2],
// ]

Parameters

Parameter	Type	Description
`$array`	`array`	Source array
`$filters`	`iterable`	Rules that define array keys which should be left or removed from results. Each rule is: - `var` - `$array['var']` will be left in result. - `var.key` = only `$array['var']['key'] will be left in result. -` !var.key`=`$array[‘var’][‘key’] will be removed from result.

Returns

array: Filtered array

Since

2.0.9

flatten()

public static function flatten(array $array, string $separator = '.'): array

Flattens a multidimensional array into a one-dimensional array.

This method recursively traverses the input array and concatenates the keys in a dot format to form a new key in the resulting array.

Example:

$array = [
     'A' => [1, 2],
     'B' => [
         'C' => 1,
         'D' => 2,
     ],
     'E' => 1,
 ];
$result = \yii\helpers\ArrayHelper::flatten($array);
// $result will be:
// [
//     'A.0' => 1
//     'A.1' => 2
//     'B.C' => 1
//     'B.D' => 2
//     'E' => 1
// ]

Parameters

Parameter	Type	Description
`$array`	`array`	The input array to be flattened in terms of name-value pairs.
`$separator`	`string`	The separator to use between keys. Defaults to ’.’.

Returns

array: The flattened array.

Throws

yii\base\InvalidArgumentException: if $array is neither traversable nor an array.

getColumn()

public static function getColumn(array $array, int|string|array|Closure $name, bool $keepKeys = true): array

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'];
});

Parameters

Parameter	Type	Description
`$array`	`array`
`$name`	`int\|string\|array\|Closure`
`$keepKeys`	`bool`	Whether to maintain the array keys. If false, the resulting array will be re-indexed with integers.

Returns

array: The list of column values

getValue()

public static function getValue(array|object $array, string|Closure|array $key, mixed $default = null): mixed

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, the default value will be returned instead. Not used when getting value from an object.

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']);

Parameters

Parameter	Type	Description
`$array`	`array\|object`	Array or object to extract value from
`$key`	`string\|Closure\|array`	Key name of the array element, an array of keys or property name of the object, or an anonymous function returning the value. The anonymous function signature should be: `function($array, $defaultValue)`. The possibility to pass an array of keys is available since version 2.0.4.
`$default`	`mixed`	The default value to be returned if the specified array key does not exist. Not used when getting value from an object.

Returns

mixed: The value of the element if found, default value otherwise

htmlDecode()

public static function htmlDecode(array $data, bool $valuesOnly = true): array

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.

Parameters

Parameter	Type	Description
`$data`	`array`	Data to be decoded
`$valuesOnly`	`bool`	Whether to decode array values only. If `false`, then both the array keys and array values will be decoded.

Returns

array: The decoded data

See also

https://www.php.net/manual/en/function.htmlspecialchars-decode.php

htmlEncode()

public static function htmlEncode(array $data, bool $valuesOnly = true, string|null $charset = null): array

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.

Parameters

Parameter	Type	Description
`$data`	`array`	Data to be encoded
`$valuesOnly`	`bool`	Whether to encode array values only. If false, both the array keys and array values will be encoded.
`$charset`	`string\|null`	The charset that the data is using. If not set, `Application::$charset` will be used.

Returns

array: The encoded data

See also

https://www.php.net/manual/en/function.htmlspecialchars.php

index()

public static function index(array $array, string|Closure|null $key, string|string[]|Closure[]|null $groups = []): array

Indexes and/or groups the array according to a specified key.

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

The $key can be either a key name of the sub-array, a property name of object, or an anonymous function that must return the value that will be used as a key.

$groups is an array of keys, that will be used to group the input array into one or more sub-arrays based on keys specified.

If the $key is specified as null or a value of an element corresponding to the key is null in addition to $groups not specified then the element is discarded.

For example:

$array = [
    ['id' => '123', 'data' => 'abc', 'device' => 'laptop'],
    ['id' => '345', 'data' => 'def', 'device' => 'tablet'],
    ['id' => '345', 'data' => 'hgi', 'device' => 'smartphone'],
];
$result = ArrayHelper::index($array, 'id');

The result will be an associative array, where the key is the value of id attribute

[
    '123' => ['id' => '123', 'data' => 'abc', 'device' => 'laptop'],
    '345' => ['id' => '345', 'data' => 'hgi', 'device' => 'smartphone']
    // The second element of an original array is overwritten by the last element because of the same id
]

An anonymous function can be used in the grouping array as well.

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

Passing id as a third argument will group $array by id:

$result = ArrayHelper::index($array, null, 'id');

The result will be a multidimensional array grouped by id:

[
    '123' => [
        ['id' => '123', 'data' => 'abc', 'device' => 'laptop']
    ],
    '345' => [ // all elements with this index are present in the result array
        ['id' => '345', 'data' => 'def', 'device' => 'tablet'],
        ['id' => '345', 'data' => 'hgi', 'device' => 'smartphone'],
    ]
]

The anonymous function can be used in the array of grouping keys as well:

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

The result will be a multidimensional array grouped by id on the first level, by the device on the second one and indexed by the data on the third level:

[
    '123' => [
        'laptop' => [
            'abc' => ['id' => '123', 'data' => 'abc', 'device' => 'laptop']
        ]
    ],
    '345' => [
        'tablet' => [
            'def' => ['id' => '345', 'data' => 'def', 'device' => 'tablet']
        ],
        'smartphone' => [
            'hgi' => ['id' => '345', 'data' => 'hgi', 'device' => 'smartphone']
        ]
    ]
]

Parameters

Parameter	Type	Description
`$array`	`array`	The array that needs to be indexed or grouped
`$key`	`string\|Closure\|null`	The column name or anonymous function which result will be used to index the array
`$groups`	`string\|string[]\|Closure[]\|null`	The array of keys, that will be used to group the input array by one or more keys. If the $key attribute or its value for the particular element is null and $groups is not defined, the array element will be discarded. Otherwise, if $groups is specified, array element will be added to the result array without any key. This parameter is available since version 2.0.8.

Returns

array: The indexed and/or grouped array

isAssociative()

public static function isAssociative(array $array, bool $allStrings = true): bool

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.

Parameters

Parameter	Type	Description
`$array`	`array`	The array being checked
`$allStrings`	`bool`	Whether the array keys must be all strings in order for the array to be treated as associative.

Returns

bool: Whether the array is associative

isIn()

public static function isIn(mixed $needle, iterable $haystack, bool $strict = false): bool

Check whether an array or Traversable contains an element.

This method does the same as the PHP function in_array() but additionally works for objects that implement the Traversable interface.

Parameters

Parameter	Type	Description
`$needle`	`mixed`	The value to look for.
`$haystack`	`iterable`	The set of values to search.
`$strict`	`bool`	Whether to enable strict (`===`) comparison.

Returns

bool: true if $needle was found in $haystack, false otherwise.

Throws

yii\base\InvalidArgumentException: if $haystack is neither traversable nor an array.

Since

2.0.7

See also

https://www.php.net/manual/en/function.in-array.php

isIndexed()

public static function isIndexed(array $array, bool $consecutive = false): bool

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.

Parameters

Parameter	Type	Description
`$array`	`array`	The array being checked
`$consecutive`	`bool`	Whether the array keys must be a consecutive sequence in order for the array to be treated as indexed.

Returns

bool: Whether the array is indexed

isSubset()

public static function isSubset(iterable $needles, iterable $haystack, bool $strict = false): bool

Checks whether an array or Traversable is a subset of another array or Traversable.

This method will return true, if all elements of $needles are contained in $haystack. If at least one element is missing, false will be returned.

Parameters

Parameter	Type	Description
`$needles`	`iterable`	The values that must all be in `$haystack`.
`$haystack`	`iterable`	The set of value to search.
`$strict`	`bool`	Whether to enable strict (`===`) comparison.

Returns

bool: true if $needles is a subset of $haystack, false otherwise.

Throws

yii\base\InvalidArgumentException: if $haystack or $needles is neither traversable nor an array.

Since

2.0.7

isTraversable()

public static function isTraversable(mixed $var): bool

Checks whether a variable is an array or Traversable.

This method does the same as the PHP function is_array() but additionally works on objects that implement the Traversable interface.

Parameters

Parameter	Type	Description
`$var`	`mixed`	The variable being evaluated.

Returns

bool: Whether $var can be traversed via foreach

Since

2.0.8

See also

https://www.php.net/manual/en/function.is-array.php

keyExists()

public static function keyExists(string|int $key, array<array-key, mixed>|ArrayAccess<array-key, mixed> $array, bool $caseSensitive = true): bool

Checks if the given array contains the specified key.

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

Parameters

Parameter	Type	Description
`$key`	`string\|int`	The key to check
`$array`	`array<array-key, mixed>\|ArrayAccess<array-key, mixed>`	The array with keys to check
`$caseSensitive`	`bool`	Whether the key comparison should be case-sensitive

Returns

bool: Whether the array contains the specified key

map()

public static function map(array $array, string|Closure $from, string|Closure $to, string|Closure|null $group = null): array

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',
//     ],
// ]

Parameters

Parameter	Type	Description
`$array`	`array`
`$from`	`string\|Closure`
`$to`	`string\|Closure`
`$group`	`string\|Closure\|null`

Returns

array

merge()

public static function merge(array<array-key, mixed> $a, array<array-key, mixed> ...$b): array<array-key, mixed>

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. You can use UnsetArrayValue object to unset value from previous array or ReplaceArrayValue to force replace former value instead of recursive merging.

Parameters

Parameter	Type	Description
`$a`	`array<array-key, mixed>`	Array to be merged to
`...$b`	`array<array-key, mixed>`	Array to be merged from. You can specify additional arrays via third argument, fourth argument etc.

Returns

array<array-key, mixed>: The merged array (the original arrays are not changed.)

multisort()

public static function multisort(array &$array, string|Closure|array $key, int|array $direction = \yii\helpers\SORT_ASC, int|array $sortFlag = \yii\helpers\SORT_REGULAR): mixed

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

Parameters

Parameter	Type	Description
`$array`	`array`	The array to be sorted. The array will be modified after calling this method.
`$key`	`string\|Closure\|array`	The key(s) to be sorted by. This refers to a key name of the sub-array elements, a property name of the objects, or an anonymous function returning the values for comparison purpose. The anonymous function signature should be: `function($item)`. To sort by multiple keys, provide an array of keys here.
`$direction`	`int\|array`	The sorting direction. It can be either `SORT_ASC` or `SORT_DESC`. When sorting by multiple keys with different sorting directions, use an array of sorting directions.
`$sortFlag`	`int\|array`	The PHP sort flag. Valid values include `SORT_REGULAR`, `SORT_NUMERIC`, `SORT_STRING`, `SORT_LOCALE_STRING`, `SORT_NATURAL` and `SORT_FLAG_CASE`. Please refer to PHP manual for more details. When sorting by multiple keys with different sort flags, use an array of sort flags.

Returns

mixed

Throws

yii\base\InvalidArgumentException: if the $direction or $sortFlag parameters do not have correct number of elements as that of $key.

recursiveSort()

public static function recursiveSort(array &$array, callable|null $sorter = null): array

Sorts array recursively.

Parameters

Parameter	Type	Description
`$array`	`array`	An array passing by reference.
`$sorter`	`callable\|null`	The array sorter. If omitted, sort index array by values, sort assoc array by keys.

Returns

array

remove()

public static function remove(array &$array, string $key, mixed $default = null): mixed|null

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]];

Parameters

Parameter	Type	Description
`$array`	`array`	The array to extract value from
`$key`	`string`	Key name of the array element
`$default`	`mixed`	The default value to be returned if the specified key does not exist

Returns

mixed|null: The value of the element if found, default value otherwise

removeValue()

public static function removeValue(array &$array, mixed $value): array

Removes items with matching values from the array and returns the removed items.

Example,

$array = ['Bob' => 'Dylan', 'Michael' => 'Jackson', 'Mick' => 'Jagger', 'Janet' => 'Jackson'];
$removed = \yii\helpers\ArrayHelper::removeValue($array, 'Jackson');
// result:
// $array = ['Bob' => 'Dylan', 'Mick' => 'Jagger'];
// $removed = ['Michael' => 'Jackson', 'Janet' => 'Jackson'];

Parameters

Parameter	Type	Description
`$array`	`array`	The array where to look the value from
`$value`	`mixed`	The value to remove from the array

Returns

array: The items that were removed from the array

Since

2.0.11

setValue()

public static function setValue(array &$array, string|array|null $path, mixed $value): mixed

Writes a value into an associative array at the key path specified.

If there is no such key path yet, it will be created recursively. If the key exists, it will be overwritten.

 $array = [
     'key' => [
         'in' => [
             'val1',
             'key' => 'val'
         ]
     ]
 ];

The result of ArrayHelper::setValue($array, 'key.in.0', ['arr' => 'val']); will be the following:

 [
     'key' => [
         'in' => [
             ['arr' => 'val'],
             'key' => 'val'
         ]
     ]
 ]

The result of ArrayHelper::setValue($array, 'key.in', ['arr' => 'val']); or ArrayHelper::setValue($array, ['key', 'in'], ['arr' => 'val']); will be the following:

 [
     'key' => [
         'in' => [
             'arr' => 'val'
         ]
     ]
 ]

Parameters

Parameter	Type	Description
`$array`	`array`	The array to write the value to
`$path`	`string\|array\|null`	The path of where do you want to write a value to `$array` the path can be described by a string when each key should be separated by a dot you can also describe the path as an array of keys if the path is null then `$array` will be assigned the `$value`
`$value`	`mixed`	The value to be written

Returns

mixed

Since

2.0.13

toArray()

public static function toArray(object|array|string $object, array $properties = [], bool $recursive = true): array

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

Parameters

Parameter	Type	Description
`$object`	`object\|array\|string`	The object to be converted into an array
`$properties`	`array`	A mapping from object class names to the properties that need to put into the resulting arrays. The properties specified for each class is an array of the following format: [ ‘app\models\Post’ => [ ‘id’, ‘title’, // the key name in array result => property name ‘createTime’ => ‘created_at’, // the key name in array result => anonymous function ‘length’ => function ($post) { return strlen($post->content); }, ], ] The result of `ArrayHelper::toArray($post, $properties)` could be like the following: [ ‘id’ => 123, ‘title’ => ‘test’, ‘createTime’ => ‘2013-01-01 12:00AM’, ‘length’ => 301, ]
`$recursive`	`bool`	Whether to recursively converts properties which are objects into arrays.

Returns

array: The array representation of the object