Php/docs/function.in-array

• PHP Manual
• Array Functions
• Checks if a value exists in an array

in_array

(PHP 4, PHP 5, PHP 7)

in_array — Checks if a value exists in an array

Description

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

Searches for needle in haystack using loose comparison unless strict is set.

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.

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";}?>

The above example will output:

  'ph' was found
  'o' was found

See Also

• array_search() - Searches the array for a given value and returns the first corresponding key if successful
• isset() - Determine if a variable is declared and is different than NULL
• array_key_exists() - Checks if the given key or index exists in the array