I have been searching all over the internet for examples of how this is done, I just must be typing the wrong keywords in. But basically Ive seen examples like node 6059

One Example that is given is this:
if ($string =~ m!(^[a-z0-9]{4})$!) {
    $string =~ tr/[a-z]/[A-Z]/;
    # do something
} else  {
    # do some error
}

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What does all that "m!(^[a-z0-9]{4})$!)" mean! I understand it wants characters a-z,0-9 only 4 characters.

Basically, all I need to do is 'validate' three variables and remove any characters besides 0-9 a-z. So very simple, but since I dont under that that '!!<_:"!@#!@" stuff, begin semi-newish still to perl, i'm totally lost.

In reply to String Validation by Trihedralguy

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