I know how to check if a string is only numbers, but how can I detect IF the string contains anything besides
[a-zA-Z0-9]

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So in other words if the string is:$string = "hello world"; then the check would be ok, but if it had:$string = "hello world!"; Then it would not because it had a ! in it. But I don't want to check just for ! or other characters, I want to make sure it ONLY has a-z, A-Z and 0 to 9 and that is it.

sort of like this:
my $string = "I am not a window washer.";
if($string =~ ?what pattern would I search for?) {
  # Oops has invalid character
} else {
  # String is perfect only alphanumeric
}

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That is what I cannot find. I have searched everywhere, for everything I can think of, like 'alphanumeric only' 'alphanumeric' 'regex alphanumeric' but I keep coming up empty handed.

Can you please point me in the right direction?

Thank you!!

In reply to check if string contains anything other than alphanumeric by Anonymous Monk

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