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.
Example
<?php $anyArray = array("Patty","Susan","Amy","Clara");
$find = "Heather"; $result = in_array($find, $anyArray);
if ($result == true){
echo "$find is in the array";
} else {
echo "$find is NOT in the array"; } ?>
Output
Heather is NOT in the array