note 113633 added to function.strstr

strstr() is not a way to avoid type-checking with strpos(). If $needle is the last character in $haystack, and testing $needle as a boolean by itself would evaluate to false, then testing strstr() as a boolean will evaluate to false (because, if successful, strstr() returns the first occurrence of $needle along with the rest of $haystack). <?php findZero('01234'); // found a zero findZero('43210'); // did not find a zero findZero('0'); // did not find a zero findZero('00'); // found a zero findZero('000'); // found a zero findZero('10'); // did not find a zero findZero('100'); // found a zero function findZero($numberString) { if (strstr($numberString, '0')) { echo 'found a zero'; } else { echo 'did not find a zero'; } } ?> Also, strstr() is far more memory-intensive than strpos(), especially with longer strings as your $haystack, so if you are not interested in the substring that strstr() returns, you shouldn't be using it anyway. There is no PHP function just to check only _if_ $needle occurs in $haystack; strpos() tells you if it _doesn't_ by returning false, but, if it does occur, it tells you _where_ it occurs as an integer, which is 0 (zero) if $needle is the first part of $haystack, which is why testing if (strpos($needle, $haystack)===false) is the only way to know for sure if $needle is not part of $haystack. My advice is to start loving type checking immediately, and to familiarize yourself with the return value of the functions you are using. Cheers. ---- Server IP: 192.41.45.150 Probable Submitter: 64.1.208.234 ---- Manual Page -- http://php.net/manual/en/function.strstr.php Edit -- https://master.php.net/note/edit/113633 Del: integrated -- https://master.php.net/note/delete/113633/integrated Del: useless -- https://master.php.net/note/delete/113633/useless Del: bad code -- https://master.php.net/note/delete/113633/bad+code Del: spam -- https://master.php.net/note/delete/113633/spam Del: non-english -- https://master.php.net/note/delete/113633/non-english Del: in docs -- https://master.php.net/note/delete/113633/in+docs Del: other reasons-- https://master.php.net/note/delete/113633 Reject -- https://master.php.net/note/reject/113633 Search -- https://master.php.net/manage/user-notes.php