3v4l.org

run code in 300+ PHP versions simultaneously
<?php $not_allowed_symbols = '[^a-z0-9:;,!\'\s*.?()"-]'; $letter = nl2br("aaa\nbbb\nccc"); print_r($letter); if(preg_match("/$not_allowed_symbols/i", $letter)){ echo "There are not allowed symbols in the text"; }else{ echo "There are allowed symbols in the text"; }
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.8 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
aaa<br /> bbb<br /> cccThere are not allowed symbols in the text
preferences:
202.06 ms | 406 KiB | 314 Q