yii2 ArrayHelper的19个函数+使用实例+功能详解

public static function toArray($object, $properties = [], $recursive = true)

public static function merge($a, $b)

public static function getValue($array, $key, $default = null)
public static function setValue(&$array, $path, $value)

public static function remove(&$array, $key, $default = null)
public static function removeValue(&$array, $value)

public static function index($array, $key, $groups = [])

public static function getColumn($array, $name, $keepKeys = true)

public static function map($array, $from, $to, $group = null)

public static function keyExists($key, $array, $caseSensitive = true)

public static function multisort(&$array, $key, $direction = SORT_ASC, $sortFlag = SORT_REGULAR)

public static function htmlEncode($data, $valuesOnly = true, $charset = null)
public static function htmlDecode($data, $valuesOnly = true)

public static function isAssociative($array, $allStrings = true)
public static function isIndexed($array, $consecutive = false)

public static function isIn($needle, $haystack, $strict = false)

public static function isTraversable($var)

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

public static function filter($array, $filters)

2、实例

<?php
/**
* @link http://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/

namespace yiihelpers;

use Yii;
use yiiaseArrayable;
use yiiaseInvalidArgumentException;

/**
* BaseArrayHelper provides concrete implementation for [[ArrayHelper]].
*
* Do not use BaseArrayHelper. Use [[ArrayHelper]] instead.
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @since 2.0
*/
class BaseArrayHelper
{
/**
* Converts an object or an array of objects into an array.
* @param object|array|string $object the object to be converted into an array
* @param array $properties a mapping from object class names to the properties that need to put into the resulting arrays.
* The properties specified for each class is an array of the following format:
*
* ```php
* [
* 'appmodelsPost' => [
* 'id',
* 'title',
* // the key name in array result => property name
* 'createTime' => 'created_at',
* // the key name in array result => anonymous function
* 'length' => function ($post) {
* return strlen($post->content);
* },
* ],
* ]
* ```
*
* The result of `ArrayHelper::toArray($post, $properties)` could be like the following:
*
* ```php
* [
* 'id' => 123,
* 'title' => 'test',
* 'createTime' => '2013-01-01 12:00AM',
* 'length' => 301,
* ]
* ```
*
* @param bool $recursive whether to recursively converts properties which are objects into arrays.
* @return array the array representation of the object
*/
public static function toArray($object, $properties = [], $recursive = true)
{
if (is_array($object)) {
if ($recursive) {
foreach ($object as $key => $value) {
if (is_array($value) || is_object($value)) {
$object[$key] = static::toArray($value, $properties, true);
}
}
}

return $object;
} elseif (is_object($object)) {
if (!empty($properties)) {
$className = get_class($object);
if (!empty($properties[$className])) {
$result = [];
foreach ($properties[$className] as $key => $name) {
if (is_int($key)) {
$result[$name] = $object->$name;
} else {
$result[$key] = static::getValue($object, $name);
}
}

return $recursive ? static::toArray($result, $properties) : $result;
}
}
if ($object instanceof Arrayable) {
$result = $object->toArray([], [], $recursive);
} else {
$result = [];
foreach ($object as $key => $value) {
$result[$key] = $value;
}
}

return $recursive ? static::toArray($result, $properties) : $result;
}

return [$object];
}

/**
* 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.
* @param array $a array to be merged to
* @param array $b array to be merged from. You can specify additional
* arrays via third argument, fourth argument etc.
* @return array the merged array (the original arrays are not changed.)
*/
public static function merge($a, $b)
{
$args = func_get_args();
$res = array_shift($args);
while (!empty($args)) {
foreach (array_shift($args) as $k => $v) {
if ($v instanceof UnsetArrayValue) {
unset($res[$k]);
} elseif ($v instanceof ReplaceArrayValue) {
$res[$k] = $v->value;
} elseif (is_int($k)) {
if (array_key_exists($k, $res)) {
$res[] = $v;
} else {
$res[$k] = $v;
}
} elseif (is_array($v) && isset($res[$k]) && is_array($res[$k])) {
$res[$k] = self::merge($res[$k], $v);
} else {
$res[$k] = $v;
}
}
}

return $res;
}

/**
* 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,
*
* ```php
* // working with array
* $username = yiihelpersArrayHelper::getValue($_POST, 'username');
* // working with object
* $username = yiihelpersArrayHelper::getValue($user, 'username');
* // working with anonymous function
* $fullName = yiihelpersArrayHelper::getValue($user, function ($user, $defaultValue) {
* return $user->firstName . ' ' . $user->lastName;
* });
* // using dot format to retrieve the property of embedded object
* $street = yiihelpersArrayHelper::getValue($users, 'address.street');
* // using an array of keys to retrieve the value
* $value = yiihelpersArrayHelper::getValue($versions, ['1.0', 'date']);
* ```
*
* @param array|object $array array or object to extract value from
* @param string|Closure|array $key key name of the array element, an array of keys or property name of the object,
* or an anonymous function returning the value. The anonymous function signature should be:
* `function($array, $defaultValue)`.
* The possibility to pass an array of keys is available since version 2.0.4.
* @param mixed $default the default value to be returned if the specified array key does not exist. Not used when
* getting value from an object.
* @return mixed the value of the element if found, default value otherwise
*/
public static function getValue($array, $key, $default = null)
{
if ($key instanceof Closure) {
return $key($array, $default);
}

if (is_array($key)) {
$lastKey = array_pop($key);
foreach ($key as $keyPart) {
$array = static::getValue($array, $keyPart);
}
$key = $lastKey;
}

if (is_array($array) && (isset($array[$key]) || array_key_exists($key, $array))) {
return $array[$key];
}

if (($pos = strrpos($key, '.')) !== false) {
$array = static::getValue($array, substr($key, 0, $pos), $default);
$key = substr($key, $pos + 1);
}

if (is_object($array)) {
// this is expected to fail if the property does not exist, or __get() is not implemented
// it is not reliably possible to check whether a property is accessible beforehand
return $array->$key;
} elseif (is_array($array)) {
return (isset($array[$key]) || array_key_exists($key, $array)) ? $array[$key] : $default;
}

return $default;
}

/**
* 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.
*
* ```php
* $array = [
* 'key' => [
* 'in' => [
* 'val1',
* 'key' => 'val'
* ]
* ]
* ];
* ```
*
* The result of `ArrayHelper::setValue($array, 'key.in.0', ['arr' => 'val']);` will be the following:
*
* ```php
* [
* '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:
*
* ```php
* [
* 'key' => [
* 'in' => [
* 'arr' => 'val'
* ]
* ]
* ]
* ```
*
* @param array $array the array to write the value to
* @param string|array|null $path the path of where do you want to write a value to `$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`
* @param mixed $value the value to be written
* @since 2.0.13
*/
public static function setValue(&$array, $path, $value)
{
if ($path === null) {
$array = $value;
return;
}

$keys = is_array($path) ? $path : explode('.', $path);

while (count($keys) > 1) {
$key = array_shift($keys);
if (!isset($array[$key])) {
$array[$key] = [];
}
if (!is_array($array[$key])) {
$array[$key] = [$array[$key]];
}
$array = &$array[$key];
}

$array[array_shift($keys)] = $value;
}

/**
* 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,
*
* ```php
* // $array = ['type' => 'A', 'options' => [1, 2]];
* // working with array
* $type = yiihelpersArrayHelper::remove($array, 'type');
* // $array content
* // $array = ['options' => [1, 2]];
* ```
*
* @param array $array the array to extract value from
* @param string $key key name of the array element
* @param mixed $default the default value to be returned if the specified key does not exist
* @return mixed|null the value of the element if found, default value otherwise
*/
public static function remove(&$array, $key, $default = null)
{
if (is_array($array) && (isset($array[$key]) || array_key_exists($key, $array))) {
$value = $array[$key];
unset($array[$key]);

return $value;
}

return $default;
}

/**
* Removes items with matching values from the array and returns the removed items.
*
* Example,
*
* ```php
* $array = ['Bob' => 'Dylan', 'Michael' => 'Jackson', 'Mick' => 'Jagger', 'Janet' => 'Jackson'];
* $removed = yiihelpersArrayHelper::removeValue($array, 'Jackson');
* // result:
* // $array = ['Bob' => 'Dylan', 'Mick' => 'Jagger'];
* // $removed = ['Michael' => 'Jackson', 'Janet' => 'Jackson'];
* ```
*
* @param array $array the array where to look the value from
* @param string $value the value to remove from the array
* @return array the items that were removed from the array
* @since 2.0.11
*/
public static function removeValue(&$array, $value)
{
$result = [];
if (is_array($array)) {
foreach ($array as $key => $val) {
if ($val === $value) {
$result[$key] = $val;
unset($array[$key]);
}
}
}

return $result;
}

/**
* 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:
*
* ```php
* $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
*
* ```php
* [
* '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.
*
* ```php
* $result = ArrayHelper::index($array, function ($element) {
* return $element['id'];
* });
* ```
*
* Passing `id` as a third argument will group `$array` by `id`:
*
* ```php
* $result = ArrayHelper::index($array, null, 'id');
* ```
*
* The result will be a multidimensional array grouped by `id` on the first level, by `device` on the second level
* and indexed by `data` on the third level:
*
* ```php
* [
* '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:
*
* ```php
* $result = ArrayHelper::index($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:
*
* ```php
* [
* '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']
* ]
* ]
* ]
* ```
*
* @param array $array the array that needs to be indexed or grouped
* @param string|Closure|null $key the column name or anonymous function which result will be used to index the array
* @param string|string[]|Closure[]|null $groups 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 $groups is specified, array element will be added
* to the result array without any key. This parameter is available since version 2.0.8.
* @return array the indexed and/or grouped array
*/
public static function index($array, $key, $groups = [])
{
$result = [];
$groups = (array) $groups;

foreach ($array as $element) {
$lastArray = &$result;

foreach ($groups as $group) {
$value = static::getValue($element, $group);
if (!array_key_exists($value, $lastArray)) {
$lastArray[$value] = [];
}
$lastArray = &$lastArray[$value];
}

if ($key === null) {
if (!empty($groups)) {
$lastArray[] = $element;
}
} else {
$value = static::getValue($element, $key);
if ($value !== null) {
if (is_float($value)) {
$value = StringHelper::floatToString($value);
}
$lastArray[$value] = $element;
}
}
unset($lastArray);
}

return $result;
}

/**
* Returns the values of a specified column in an array.
* The input array should be multidimensional or an array of objects.
*
* For example,
*
* ```php
* $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'];
* });
* ```
*
* @param array $array
* @param string|Closure $name
* @param bool $keepKeys whether to maintain the array keys. If false, the resulting array
* will be re-indexed with integers.
* @return array the list of column values
*/
public static function getColumn($array, $name, $keepKeys = true)
{
$result = [];
if ($keepKeys) {
foreach ($array as $k => $element) {
$result[$k] = static::getValue($element, $name);
}
} else {
foreach ($array as $element) {
$result[] = static::getValue($element, $name);
}
}

return $result;
}

/**
* 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,
*
* ```php
* $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',
* // ],
* // ]
* ```
*
* @param array $array
* @param string|Closure $from
* @param string|Closure $to
* @param string|Closure $group
* @return array
*/
public static function map($array, $from, $to, $group = null)
{
$result = [];
foreach ($array as $element) {
$key = static::getValue($element, $from);
$value = static::getValue($element, $to);
if ($group !== null) {
$result[static::getValue($element, $group)][$key] = $value;
} else {
$result[$key] = $value;
}
}

return $result;
}

/**
* Checks if the given array contains the specified key.
* This method enhances the `array_key_exists()` function by supporting case-insensitive
* key comparison.
* @param string $key the key to check
* @param array $array the array with keys to check
* @param bool $caseSensitive whether the key comparison should be case-sensitive
* @return bool whether the array contains the specified key
*/
public static function keyExists($key, $array, $caseSensitive = true)
{
if ($caseSensitive) {
// Function `isset` checks key faster but skips `null`, `array_key_exists` handles this case
// http://php.net/manual/en/function.array-key-exists.php#107786
return isset($array[$key]) || array_key_exists($key, $array);
}

foreach (array_keys($array) as $k) {
if (strcasecmp($key, $k) === 0) {
return true;
}
}

return false;
}

/**
* Sorts an array of objects or arrays (with the same structure) by one or several keys.
* @param array $array the array to be sorted. The array will be modified after calling this method.
* @param string|Closure|array $key the key(s) to be sorted by. This refers to a key name of the sub-array
* elements, a property name of the objects, or an anonymous function returning the values for comparison
* purpose. The anonymous function signature should be: `function($item)`.
* To sort by multiple keys, provide an array of keys here.
* @param int|array $direction 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.
* @param int|array $sortFlag 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](http://php.net/manual/en/function.sort.php)
* for more details. When sorting by multiple keys with different sort flags, use an array of sort flags.
* @throws InvalidArgumentException if the $direction or $sortFlag parameters do not have
* correct number of elements as that of $key.
*/
public static function multisort(&$array, $key, $direction = SORT_ASC, $sortFlag = SORT_REGULAR)
{
$keys = is_array($key) ? $key : [$key];
if (empty($keys) || empty($array)) {
return;
}
$n = count($keys);
if (is_scalar($direction)) {
$direction = array_fill(0, $n, $direction);
} elseif (count($direction) !== $n) {
throw new InvalidArgumentException('The length of $direction parameter must be the same as that of $keys.');
}
if (is_scalar($sortFlag)) {
$sortFlag = array_fill(0, $n, $sortFlag);
} elseif (count($sortFlag) !== $n) {
throw new InvalidArgumentException('The length of $sortFlag parameter must be the same as that of $keys.');
}
$args = [];
foreach ($keys as $i => $key) {
$flag = $sortFlag[$i];
$args[] = static::getColumn($array, $key);
$args[] = $direction[$i];
$args[] = $flag;
}

// This fix is used for cases when main sorting specified by columns has equal values
// Without it it will lead to Fatal Error: Nesting level too deep - recursive dependency?
$args[] = range(1, count($array));
$args[] = SORT_ASC;
$args[] = SORT_NUMERIC;

$args[] = &$array;
call_user_func_array('array_multisort', $args);
}

/**
* 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.
* @param array $data data to be encoded
* @param bool $valuesOnly whether to encode array values only. If false,
* both the array keys and array values will be encoded.
* @param string $charset the charset that the data is using. If not set,
* [[yiiaseApplication::charset]] will be used.
* @return array the encoded data
* @see http://www.php.net/manual/en/function.htmlspecialchars.php
*/
public static function htmlEncode($data, $valuesOnly = true, $charset = null)
{
if ($charset === null) {
$charset = Yii::$app ? Yii::$app->charset : 'UTF-8';
}
$d = [];
foreach ($data as $key => $value) {
if (!$valuesOnly && is_string($key)) {
$key = htmlspecialchars($key, ENT_QUOTES | ENT_SUBSTITUTE, $charset);
}
if (is_string($value)) {
$d[$key] = htmlspecialchars($value, ENT_QUOTES | ENT_SUBSTITUTE, $charset);
} elseif (is_array($value)) {
$d[$key] = static::htmlEncode($value, $valuesOnly, $charset);
} else {
$d[$key] = $value;
}
}

return $d;
}

/**
* 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.
* @param array $data data to be decoded
* @param bool $valuesOnly whether to decode array values only. If false,
* both the array keys and array values will be decoded.
* @return array the decoded data
* @see http://www.php.net/manual/en/function.htmlspecialchars-decode.php
*/
public static function htmlDecode($data, $valuesOnly = true)
{
$d = [];
foreach ($data as $key => $value) {
if (!$valuesOnly && is_string($key)) {
$key = htmlspecialchars_decode($key, ENT_QUOTES);
}
if (is_string($value)) {
$d[$key] = htmlspecialchars_decode($value, ENT_QUOTES);
} elseif (is_array($value)) {
$d[$key] = static::htmlDecode($value);
} else {
$d[$key] = $value;
}
}

return $d;
}

/**
* 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.
*
* @param array $array the array being checked
* @param bool $allStrings whether the array keys must be all strings in order for
* the array to be treated as associative.
* @return bool whether the array is associative
*/
public static function isAssociative($array, $allStrings = true)
{
if (!is_array($array) || empty($array)) {
return false;
}

if ($allStrings) {
foreach ($array as $key => $value) {
if (!is_string($key)) {
return false;
}
}

return true;
}

foreach ($array as $key => $value) {
if (is_string($key)) {
return true;
}
}

return false;
}

/**
* 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.
*
* @param array $array the array being checked
* @param bool $consecutive whether the array keys must be a consecutive sequence
* in order for the array to be treated as indexed.
* @return bool whether the array is indexed
*/
public static function isIndexed($array, $consecutive = false)
{
if (!is_array($array)) {
return false;
}

if (empty($array)) {
return true;
}

if ($consecutive) {
return array_keys($array) === range(0, count($array) - 1);
}

foreach ($array as $key => $value) {
if (!is_int($key)) {
return false;
}
}

return true;
}

/**
* Check whether an array or [[Traversable]] contains an element.
*
* This method does the same as the PHP function [in_array()](http://php.net/manual/en/function.in-array.php)
* but additionally works for objects that implement the [[Traversable]] interface.
* @param mixed $needle The value to look for.
* @param array|Traversable $haystack The set of values to search.
* @param bool $strict Whether to enable strict (`===`) comparison.
* @return bool `true` if `$needle` was found in `$haystack`, `false` otherwise.
* @throws InvalidArgumentException if `$haystack` is neither traversable nor an array.
* @see http://php.net/manual/en/function.in-array.php
* @since 2.0.7
*/
public static function isIn($needle, $haystack, $strict = false)
{
if ($haystack instanceof Traversable) {
foreach ($haystack as $value) {
if ($needle == $value && (!$strict || $needle === $value)) {
return true;
}
}
} elseif (is_array($haystack)) {
return in_array($needle, $haystack, $strict);
} else {
throw new InvalidArgumentException('Argument $haystack must be an array or implement Traversable');
}

return false;
}

/**
* Checks whether a variable is an array or [[Traversable]].
*
* This method does the same as the PHP function [is_array()](http://php.net/manual/en/function.is-array.php)
* but additionally works on objects that implement the [[Traversable]] interface.
* @param mixed $var The variable being evaluated.
* @return bool whether $var is array-like
* @see http://php.net/manual/en/function.is-array.php
* @since 2.0.8
*/
public static function isTraversable($var)
{
return is_array($var) || $var instanceof Traversable;
}

/**
* 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.
* @param array|Traversable $needles The values that must **all** be in `$haystack`.
* @param array|Traversable $haystack The set of value to search.
* @param bool $strict Whether to enable strict (`===`) comparison.
* @throws InvalidArgumentException if `$haystack` or `$needles` is neither traversable nor an array.
* @return bool `true` if `$needles` is a subset of `$haystack`, `false` otherwise.
* @since 2.0.7
*/
public static function isSubset($needles, $haystack, $strict = false)
{
if (is_array($needles) || $needles instanceof Traversable) {
foreach ($needles as $needle) {
if (!static::isIn($needle, $haystack, $strict)) {
return false;
}
}

return true;
}

throw new InvalidArgumentException('Argument $needles must be an array or implement Traversable');
}

/**
* Filters array according to rules specified.
*
* For example:
*
* ```php
* $array = [
* 'A' => [1, 2],
* 'B' => [
* 'C' => 1,
* 'D' => 2,
* ],
* 'E' => 1,
* ];
*
* $result = yiihelpersArrayHelper::filter($array, ['A']);
* // $result will be:
* // [
* // 'A' => [1, 2],
* // ]
*
* $result = yiihelpersArrayHelper::filter($array, ['A', 'B.C']);
* // $result will be:
* // [
* // 'A' => [1, 2],
* // 'B' => ['C' => 1],
* // ]
*
* $result = yiihelpersArrayHelper::filter($array, ['B', '!B.C']);
* // $result will be:
* // [
* // 'B' => ['D' => 2],
* // ]
* ```
*
* @param array $array Source array
* @param array $filters Rules that define array keys which should be left or removed from results.
* Each rule is:
* - `var` - `$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.
* @return array Filtered array
* @since 2.0.9
*/
public static function filter($array, $filters)
{
$result = [];
$forbiddenVars = [];

foreach ($filters as $var) {
$keys = explode('.', $var);
$globalKey = $keys[0];
$localKey = isset($keys[1]) ? $keys[1] : null;

if ($globalKey[0] === '!') {
$forbiddenVars[] = [
substr($globalKey, 1),
$localKey,
];
continue;
}

if (!array_key_exists($globalKey, $array)) {
continue;
}
if ($localKey === null) {
$result[$globalKey] = $array[$globalKey];
continue;
}
if (!isset($array[$globalKey][$localKey])) {
continue;
}
if (!array_key_exists($globalKey, $result)) {
$result[$globalKey] = [];
}
$result[$globalKey][$localKey] = $array[$globalKey][$localKey];
}

foreach ($forbiddenVars as $var) {
list($globalKey, $localKey) = $var;
if (array_key_exists($globalKey, $result)) {
unset($result[$globalKey][$localKey]);
}
}

return $result;
}
}

原文地址:https://www.cnblogs.com/jjchi/p/9446264.html