Php where value in array

Как сделать поиск в php массиве по значению

Можно использовать встроенную функцию array_search() , она возвращает ключ найденного элемента. Затем мы можем получить и сам элемент по этому ключу.

 $numbers = [1, 2, 'salad', 'potato']; $potatoIndex = array_search('potato', $numbers); // 3 print_r($numbers[$potatoIndex]); //=> potato 

Поиск значения с помощью цикла foreach() .

Если значение подразумевает не полное соответствие, а частичное, то применяют обычно цикл с проверкой на вхождение искомого значения в значениях массива:

 $array = [ 'key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', ]; $result = ''; foreach ($array as $value)  if (str_contains($value, '5'))  $result = $value; > > echo($result); // => value5 

Источник

in_array

Ищет в haystack значение needle . Если strict не установлен, то при поиске будет использовано нестрогое сравнение.

Список параметров

Замечание:

Если needle — строка, сравнение будет произведено с учетом регистра.

Если третий параметр strict установлен в TRUE тогда функция in_array() также проверит соответствие типов параметра needle и соответствующего значения массива haystack .

Возвращаемые значения

Возвращает TRUE , если needle был найден в массиве, и FALSE в обратном случае.

Примеры

Пример #1 Пример использования in_array()

$os = array( «Mac» , «NT» , «Irix» , «Linux» );
if ( in_array ( «Irix» , $os )) echo «Нашел Irix» ;
>
if ( in_array ( «mac» , $os )) echo «Нашел mac» ;
>
?>

Второго совпадения не будет, потому что in_array() регистрозависима, таким образом, программа выведет:

Пример #2 Пример использования in_array() с параметром strict

if ( in_array ( ‘12.4’ , $a , true )) echo «‘12.4’ найдено со строгой проверкой\n» ;
>

if ( in_array ( 1.13 , $a , true )) echo «1.13 найдено со строгой проверкой\n» ;
>
?>

Результат выполнения данного примера:

1.13 найдено со строгой проверкой

Пример #3 Пример использования in_array() с массивом в качестве параметра needle

if ( in_array (array( ‘p’ , ‘h’ ), $a )) echo «‘ph’ найдено\n» ;
>

if ( in_array (array( ‘f’ , ‘i’ ), $a )) echo «‘fi’ найдено\n» ;
>

if ( in_array ( ‘o’ , $a )) echo «‘o’ найдено\n» ;
>
?>

Результат выполнения данного примера:

Смотрите также

• array_search() — Осуществляет поиск данного значения в массиве и возвращает соответствующий ключ в случае удачи
• isset() — Определяет, была ли установлена переменная значением отличным от NULL
• array_key_exists() — Проверяет, присутствует ли в массиве указанный ключ или индекс

Источник

array_search

Note:

If needle is a string, the comparison is done in a case-sensitive manner.

If the third parameter strict is set to true then the array_search() function will search for identical elements in the haystack . This means it will also perform a strict type comparison of the needle in the haystack , and objects must be the same instance.

Return Values

Returns the key for needle if it is found in the array, false otherwise.

If needle is found in haystack more than once, the first matching key is returned. To return the keys for all matching values, use array_keys() with the optional search_value parameter instead.

This function may return Boolean false , but may also return a non-Boolean value which evaluates to false . Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

Examples

Example #1 array_search() example

$array = array( 0 => ‘blue’ , 1 => ‘red’ , 2 => ‘green’ , 3 => ‘red’ );

$key = array_search ( ‘green’ , $array ); // $key = 2;
$key = array_search ( ‘red’ , $array ); // $key = 1;
?>

See Also

• array_keys() — Return all the keys or a subset of the keys of an array
• array_values() — Return all the values of an array
• array_key_exists() — Checks if the given key or index exists in the array
• in_array() — Checks if a value exists in an array

User Contributed Notes 16 notes

About searcing in multi-dimentional arrays; two notes on «xfoxawy at gmail dot com»;

It perfectly searches through multi-dimentional arrays combined with array_column() (min php 5.5.0) but it may not return the values you’d expect.

Since array_column() will produce a resulting array; it won’t preserve your multi-dimentional array’s keys. So if you check against your keys, it will fail.

$people = array(
2 => array(
‘name’ => ‘John’ ,
‘fav_color’ => ‘green’
),
5 => array(
‘name’ => ‘Samuel’ ,
‘fav_color’ => ‘blue’
)
);

$found_key = array_search ( ‘blue’ , array_column ( $people , ‘fav_color’ ));
?>

Here, you could expect that the $found_key would be «5» but it’s NOT. It will be 1. Since it’s the second element of the produced array by the array_column() function.

Secondly, if your array is big, I would recommend you to first assign a new variable so that it wouldn’t call array_column() for each element it searches. For a better performance, you could do;

$colors = array_column ( $people , ‘fav_color’ );
$found_key = array_search ( ‘blue’ , $colors );
?>

If you are using the result of array_search in a condition statement, make sure you use the === operator instead of == to test whether or not it found a match. Otherwise, searching through an array with numeric indicies will result in index 0 always getting evaluated as false/null. This nuance cost me a lot of time and sanity, so I hope this helps someone. In case you don’t know what I’m talking about, here’s an example:

$code = array( «a» , «b» , «a» , «c» , «a» , «b» , «b» ); // infamous abacabb mortal kombat code 😛

// this is WRONG
while (( $key = array_search ( «a» , $code )) != NULL )
<
// infinite loop, regardless of the unset
unset( $code [ $key ]);
>

// this is _RIGHT_
while (( $key = array_search ( «a» , $code )) !== NULL )
<
// loop will terminate
unset( $code [ $key ]);
>
?>

for searching case insensitive better this:

array_search ( strtolower ( $element ), array_map ( ‘strtolower’ , $array ));
?>

var_dump ( array_search ( ‘needle’ , [ 0 => 0 ])); // int(0) (!)

var_dump ( array_search ( ‘needle’ , [ 0 => 0 ], true )); // bool(false)

var_dump ( array_search ( ‘needle’ , [ 0 => 0 ])); // bool(false)

To expand on previous comments, here are some examples of
where using array_search within an IF statement can go
wrong when you want to use the array key thats returned.

Take the following two arrays you wish to search:

$fruit_array = array( «apple» , «pear» , «orange» );
$fruit_array = array( «a» => «apple» , «b» => «pear» , «c» => «orange» );

if ( $i = array_search ( «apple» , $fruit_array ))
//PROBLEM: the first array returns a key of 0 and IF treats it as FALSE

if ( is_numeric ( $i = array_search ( «apple» , $fruit_array )))
//PROBLEM: works on numeric keys of the first array but fails on the second

if ( $i = is_numeric ( array_search ( «apple» , $fruit_array )))
//PROBLEM: using the above in the wrong order causes $i to always equal 1

if ( $i = array_search ( «apple» , $fruit_array ) !== FALSE )
//PROBLEM: explicit with no extra brackets causes $i to always equal 1

if (( $i = array_search ( «apple» , $fruit_array )) !== FALSE )
//YES: works on both arrays returning their keys
?>

Despite PHP’s amazing assortment of array functions and juggling maneuvers, I found myself needing a way to get the FULL array key mapping to a specific value. This function does that, and returns an array of the appropriate keys to get to said (first) value occurrence.

function array_recursive_search_key_map($needle, $haystack) foreach($haystack as $first_level_key=>$value) if ($needle === $value) return array($first_level_key);
> elseif (is_array($value)) $callback = array_recursive_search_key_map($needle, $value);
if ($callback) return array_merge(array($first_level_key), $callback);
>
>
>
return false;
>

$nested_array = $sample_array = array(
‘a’ => array(
‘one’ => array (‘aaa’ => ‘apple’, ‘bbb’ => ‘berry’, ‘ccc’ => ‘cantalope’),
‘two’ => array (‘ddd’ => ‘dog’, ‘eee’ => ‘elephant’, ‘fff’ => ‘fox’)
),
‘b’ => array(
‘three’ => array (‘ggg’ => ‘glad’, ‘hhh’ => ‘happy’, ‘iii’ => ‘insane’),
‘four’ => array (‘jjj’ => ‘jim’, ‘kkk’ => ‘kim’, ‘lll’ => ‘liam’)
),
‘c’ => array(
‘five’ => array (‘mmm’ => ‘mow’, ‘nnn’ => ‘no’, ‘ooo’ => ‘ohh’),
‘six’ => array (‘ppp’ => ‘pidgeon’, ‘qqq’ => ‘quail’, ‘rrr’ => ‘rooster’)
)
);

$array_keymap = array_recursive_search_key_map($search_value, $nested_array);

But again, with the above solution, PHP again falls short on how to dynamically access a specific element’s value within the nested array. For that, I wrote a 2nd function to pull the value that was mapped above.

function array_get_nested_value($keymap, $array)
$nest_depth = sizeof($keymap);
$value = $array;
for ($i = 0; $i < $nest_depth; $i++) $value = $value[$keymap[$i]];
>

usage example:
——————-
echo array_get_nested_value($array_keymap, $nested_array); // insane

Источник

PHP in_array

Summary: in this tutorial, you will learn how to use the PHP in_array() function to check if a value exists in an array.

Introduction to the PHP in_array() function

The in_array() function returns true if a value exists in an array. Here’s the syntax of the in_array() function:

in_array ( mixed $needle , array $haystack , bool $strict = false ) : boolCode language: PHP (php)

• $needle is the searched value.
• $haystack is the array to search.
• $strict if the $strict sets to true , the in_array() function will use the strict comparison.

The in_array() function searches for the $needle in the $haystack using the loose comparison ( == ). To use the strict comparison ( === ), you need to set the $strict argument to true .

If the value to check is a string, the in_array() function will search for it case-sensitively.

The in_array() function returns true if the $needle exists in the $array ; otherwise, it returns false .

PHP in_array() function examples

Let’s take some examples of using the in_array() function.

1) Simple PHP in_array() function examples

The following example uses the in_array() function to check if the value ‘update’ is in the $actions array:

 $actions = [ 'new', 'edit', 'update', 'view', 'delete', ]; $result = in_array('update', $actions); var_dump($result); // bool(true)Code language: HTML, XML (xml)

The following example returns false because the publish value doesn’t exist in the $actions array:

 $actions = [ 'new', 'edit', 'update', 'view', 'delete', ]; $result = in_array('publish', $actions); var_dump($result); // bool(false) Code language: HTML, XML (xml)

The following example returns false because the value ‘New’ doesn’t exist in the $actions array. Note that the in_array() compares the strings case-sensitively:

 $actions = [ 'new', 'edit', 'update', 'view', 'delete', ]; $result = in_array('New', $actions); var_dump($result); // bool(false) Code language: HTML, XML (xml)

2) Using PHP in_array() function with the strict comparison example

The following example uses the in_array() function to find the number 15 in the $user_ids array. It returns true because the in_array() function compares the values using the loose comparison ( == ):

 $user_ids = [10, '15', '20', 30]; $result = in_array(15, $user_ids); var_dump($result); // bool(true)Code language: HTML, XML (xml)

To use the strict comparison, you pass false to the third argument ( $strict ) of the in_array() function as follows:

 $user_ids = [10, '15', '20', 30]; $result = in_array(15, $user_ids, true); var_dump($result); // bool(false)Code language: HTML, XML (xml)

This time the in_array() function returns false instead.

3) Using PHP in_array() function with the searched value is an array example

The following example uses the in_array() function with the searched value is an array:

 $colors = [ ['red', 'green', 'blue'], ['cyan', 'magenta', 'yellow', 'black'], ['hue', 'saturation', 'lightness'] ]; if (in_array(['red', 'green', 'blue'], $colors)) < echo 'RGB colors found'; > else < echo 'RGB colors are not found'; >Code language: HTML, XML (xml)

4) Using PHP in_array() function with an array of objects example

The following defines the Role class that has two properties $id and $name :

 class Role < private $id; private $name; public function __construct($id, $name) < $this->id = $id; $this->name = $name; > >Code language: HTML, XML (xml)

This example illustrates how to use the in_array() function to check if a Role object exists in an array of Role objects:

 // Role class $roles = [ new Role(1, 'admin'), new Role(2, 'editor'), new Role(3, 'subscribe'), ]; if (in_array(new Role(1, 'admin'), $roles)) < echo 'found it'; >Code language: HTML, XML (xml)

If you set the $strict to true , the in_array() function will compare objects using their identities instead of values. For example:

// Role class $roles = [ new Role(1, 'admin'), new Role(2, 'editor'), new Role(3, 'subscribe'), ]; if (in_array(new Role(1, 'admin'), $roles, true)) < echo 'found it!'; > else < echo 'not found!'; >Code language: PHP (php)

Summary

Источник