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<?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"; }

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