php man page for in_array

IN_ARRAY(3)								 1							       IN_ARRAY(3)

in_array - Checks if a value exists in an array

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

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

PARAMETERS
	      o $needle
		- The searched value.

	      Note

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

	      o $haystack
		- The array.

	      o $strict
		-  If  the  third  parameter  $strict is set to TRUE then the in_array(3) 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(3) 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(3) is case-sensitive, so the program above will display:

	      Got Irix

       Example #2

	      in_array(3) 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
";
	      }

	      if (in_array(1.13, $a, true)) {
		  echo "1.13 found with strict check
";
	      }
	      ?>

	      The above example will output:

	      1.13 found with strict check

       Example #3

	      in_array(3) 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
";
	      }

	      if (in_array(array('f', 'i'), $a)) {
		  echo "'fi' was found
";
	      }

	      if (in_array('o', $a)) {
		  echo "'o' was found
";
	      }
	      ?>

	      The above example will output:

		'o' was found

SEE ALSO
       array_search(3), isset(3), array_key_exists(3).

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