if ($string =~ /[^A-Z0-9]/) {
   # String contains a character other than A-Z, 0-9.
   ...
} else {
   # String only contains characters A-Z, 0-9.
   ...
}

[download]

or 

if ($string =~ /^[A-Z0-9]*\z/) {
   # String only contains characters A-Z, 0-9.
   ...
} else {
   # String contains a character other than A-Z, 0-9.
   ...
}

[download]

In reply to Re^2: String Validation by ikegami
in thread String Validation by Trihedralguy

Title:
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