Does array element contain substring? [duplicate]

Loop through the $forbiddennames array and use stripos to check if the given input string matches any of the items in the array:

function is_forbidden($forbiddennames, $stringtocheck) {    foreach ($forbiddennames as $name) {        if (stripos($stringtocheck, $name) !== FALSE) {            return true;        }    }}

And use it like below:

if(is_forbidden($forbiddennames, $stringtocheck)) {    echo "This is a forbidden username.";} else {    echo "True";}

Demo!

foreach ($forbiddennames as $forbiddenname) {    $nametocheck = strtolower($stringtocheck);    if(strpos($stringtocheck, $forbiddenname) !== false) {        echo "This is a forbidden username.";        break;    }}

It doesn't really matter if you use array_map, foreach or something different. Possible solution:

$forbiddenNames = array('admin', 'bannedName');$input = 'Admin12';$allowed = true;foreach($forbiddenNames as $forbiddenName) {    if(stripos($input, $forbiddenName) !== false) {        echo $input, ' is invalid';        $allowed = false;        break;    }}if($allowed === true) {    echo $input, ' is valid';}