Username Rules for New Registrations
Requires new usernames to be a sensible length, use only letters, numbers, dots, dashes and underscores, and not be just a number.
Opens WPIDE on
Code
$wpide_username_min = 4;
$wpide_username_max = 30;
add_filter( 'registration_errors', function ( $errors, $login ) use ( $wpide_username_min, $wpide_username_max ) {
$length = strlen( $login );
if ( $length < $wpide_username_min || $length > $wpide_username_max ) {
$errors->add( 'wpide_username_length', sprintf( '<strong>Error:</strong> Usernames must be between %d and %d characters.', $wpide_username_min, $wpide_username_max ) );
}
if ( ! preg_match( '/^[A-Za-z0-9._-]+$/', $login ) ) {
$errors->add( 'wpide_username_chars', '<strong>Error:</strong> Usernames may only use letters, numbers, dots, dashes and underscores.' );
} elseif ( ctype_digit( $login ) ) {
$errors->add( 'wpide_username_digits', '<strong>Error:</strong> Usernames cannot be only numbers.' );
}
return $errors;
}, 10, 2 );Notes
Existing usernames are not affected. Adjust the length limits at the top.
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