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PHP in_array() Function

Definition and Usage

The in_array() function searches an array for a specific value.

This function returns TRUE if the value is found in the array, or FALSE otherwise.

Syntax

in_array(search,array,type)

Parameter	Description
search	Required. Specifies the what to search for
array	Required. Specifies the array to search
type	Optional. If this parameter is set, the in_array() function searches for the search-string and specific type in the array

Tips and Notes

Note: If the search parameter is a string and the type parameter is set to TRUE, the search is case-sensitive.

Example 1

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland");

if (in_array("Glenn",$people))
  {
  echo "Match found";
  }
else
  {
  echo "Match not found";
  }
?>

The output of the code above will be:

Match found

Example 2

<?php
$people = array("Peter", "Joe", "Glenn", "Cleveland", 23);

if (in_array("23",$people, TRUE))
  {
  echo "Match found<br />";
  }
else
  {
  echo "Match not found<br />";
  }

if (in_array("Glenn",$people, TRUE))
  {
  echo "Match found<br />";
  }
else
  {
  echo "Match not found<br />";
  }

if (in_array(23,$people, TRUE))
  {
  echo "Match found<br />";
  }
else
  {
  echo "Match not found<br />";
  }
?>

The output of the code above will be:

Match not found
Match found
Match found

Complete PHP Array Reference