how to match string?

[michael12]

If I want to filter the string which has only character(A-z) or number (0-9), and ignore all the others, how can I do that?
for example: valid string is: aVc, a55,Zf2,4r4
invalid: a$g,4_y

 

[justice41]

The regex character class \w matches what you want except for the underscore char, '_', so if you match [tt][\W_][/tt], which is non \w characters plus the underscore then that is what you want to exclude. So any string that contains only the negation of that class is a valid string. (follow? I don't.) Here's the regex:

     if ( $string =~ /^[^\W_]+$/ ) {
        
        # Do what you want with the valid string here
        print "Good: $string\n";

    }

jaa