Question

good evening,

i need to check if the input match my regex or not

i use this pattern '@^[a-zA-Z\@]{3,30}$@is'

<?php
if( preg_match('@^[a-zA-Z\@]{3,30}$@is', 'input@input') ){ echo 'matched'; }else{ echo 'no match'; }
?>

if i removed the @ char the regex still return TRUE

<?php
if( preg_match('@^[a-zA-Z\@]{3,30}$@is', 'inputinput') ){ echo 'matched'; }else{ echo 'no match'; }
?>

i need to edit the regex so it should contain the @ char

Answer 1

You can use a look-ahead assertion to assert that:

/^(?=[^@]*@)[a-zA-Z@]{3,30}$/is

Here the look-ahead assertion (?=[^@]*@) ensures that there is at least one @.