The easiest way is not to try to look for all the weird characters, but instead to look for only the permitted characters and invert the test. If, for example, you only permit letters, numbers and commas, you would do something like ... 
if($text !~ /^[a-z0-9,]*$/i) {
    die "bad characters\n";
}

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Doing it this way ensures that you only permit what you want. This is good practice, because you won't accidentally let bad stuff through. If you try to think of all the weird characters that someone can type you're *bound* to forget some of them. For example, you're probably thinking of banning é, è, ñ and ç. But had you remembered æ, œ, ß, ð, ø, å, ł and þ?

In reply to Re: Regex for weird characters by DrHyde
in thread Regex for weird characters by Anonymous Monk

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