PHP: Checks if a value exists in an array

Description

bool in_array ( mixed $needle , array $haystack [, bool $strict ] )

Searches haystack for needle .

Parameters

needle: The searched value.

Note: If needle is a string, the comparison is done in a case-sensitive manner.
haystack: The array.
strict: If the third parameter strict is set to TRUE then the in_array() function will also check the types of the needle in the haystack .

Return Values

Returns TRUE if needle is found in the array, FALSE otherwise.

ChangeLog

Version Description

4.2.0 needle may now be an array.

Examples

Example #1 in_array() example


<?php

$os = array("Mac", "NT", "Irix", "Linux");

if (in_array("Irix", $os)) {

    echo "Got Irix";

}

if (in_array("mac", $os)) {

    echo "Got mac";

}

?>

The second condition fails because in_array() is case-sensitive, so the program above will display:

Got Irix

Example #2 in_array() with strict example


<?php

$a = array('1.10', 12.4, 1.13);



if (in_array('12.4', $a, true)) {

    echo "'12.4' found with strict check\n";

}



if (in_array(1.13, $a, true)) {

    echo "1.13 found with strict check\n";

}

?>

The above example will output:

1.13 found with strict check

Example #3 in_array() with an array as needle


<?php

$a = array(array('p', 'h'), array('p', 'r'), 'o');



if (in_array(array('p', 'h'), $a)) {

    echo "'ph' was found\n";

}



if (in_array(array('f', 'i'), $a)) {

    echo "'fi' was found\n";

}



if (in_array('o', $a)) {

    echo "'o' was found\n";

}

?>