note 105178 added to function.in-array

Be VERY careful about testing for strings in arrays that might also contain integers. In this snippet, the range() function turns the numeric values into integers, and loose data typing finds a match with zero. Outputs: PHP in_array() FOUND @#%?!! @#%?!! == 0 AT POSITION 26 BECAUSE OF LOOSE TYPE <?php // RAY_temp_in_array.php error_reporting(E_ALL); echo "<pre>"; // THE ALLOWABLE SELECTIONS $alpha = range('A','Z'); $alpha = array_merge($alpha, range('0', '9')); // LOOK FOR A BOGUS SELECTION $str = '@#%?!!'; if (in_array($str, $alpha)) { echo "PHP in_array() FOUND $str "; } else { echo "$str IS NOT IN ARRAY"; } // SEARCH THE ARRAY FOR THE KEY OF THE STRING $key = array_search($str, $alpha); echo "<br/>$str == $alpha[$key] AT POSITION $key"; if ($str == 0) echo " BECAUSE OF LOOSE TYPE"; ---- Server IP: 69.147.83.197 Probable Submitter: 98.169.58.122 ---- Manual Page -- http://www.php.net/manual/en/function.in-array.php Edit -- https://master.php.net/note/edit/105178 Del: integrated -- https://master.php.net/note/delete/105178/integrated Del: useless -- https://master.php.net/note/delete/105178/useless Del: bad code -- https://master.php.net/note/delete/105178/bad+code Del: spam -- https://master.php.net/note/delete/105178/spam Del: non-english -- https://master.php.net/note/delete/105178/non-english Del: in docs -- https://master.php.net/note/delete/105178/in+docs Del: other reasons-- https://master.php.net/note/delete/105178 Reject -- https://master.php.net/note/reject/105178 Search -- https://master.php.net/manage/user-notes.php