Your syntax is not too off, what you need to do is use the -attributes arg available in CGI.pm 2.93

6.  The optional sixth parameter (-attributes) is pro-
    vided to assign any of the common HTML attributes
    to an individual menu item. It's a pointer to an
    associative array relating menu values to another
    associative array with the attribute's name as the
    key and the attribute's value as the value.

print radio_group(
   -name    => 'type',
   -values  => [qw(old new)],
   -default => 'old',
   -labels  => {old=>'Current Device Type', new=>'Add Device Type'},
   -attributes => {
      old => {onClick=>"alert('Current');"},
      new => {onClick=>"alert('Add');"},
   }
);
[download]

And my apologies for missing the real question the first time.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)