こんなかんじになった
my %table = (
"takeshi","name",
"hanako","email",
"timpoko","sub",
"miku","comment",
"d250g2","url",
"setubun","captcha",
);
my $a = $key;
if (exists($table{$key})) {
$a = $table{$key};
}
@akkiesoft あーこれ元のパラメータ入ってた時の防御がないな