use vars qw(%Actions);
%Actions = (
  read => {
    subroutine => \&ReadData,
    template => 'readData_template',
  },
  sendmail => {
    subroutine => \&SendMail,
    template => 'sendMail_template',
  },
  # ....
  default => {
    subroutine => \&Default,
    template => 'startPage_template',
  },
); # Actions

my $cgi = CGI->new();
my $action = $cgi->param('action') || 'default';
if (exists $Actions{$action}->{subroutine} ) {
  $Actions{$action}->{subroutine}->($cgi, $action);
}
else {
  $Actions{default}->{subroutine}->($cgi, $action);
}