Hi, Thanks for directing me to good source. Anyway, I wrote a simple perl code. here' my code.

#!/usr/bin/perl
use CGI ':standard';
use strict;
use warnings;
use CGI::Carp 'fatalsToBrowser'; # use only for testing
use Encode qw(encode decode);
no warnings 'utf8'; 

print "Content-Type: text/html; charset=utf-8\n\n";

my $subject = "Room Rush \303\242\302\200\302\223 Enjoy 25% off on you
+r stay. (raw: Room Rush =?utf-8?b?4oCT?= Enjoy 25% off on your stay.)
+";

$subject =~ s/[^[:ascii:]]+//g;  # get rid of non-ASCII characters

my $subject_decoded = decode("MIME-Header", $subject);
#my $subject_decoded = decode("MIME-B", $subject);
#my $subject_decoded = decode("MIME-Q", $subject);

print "\n";
print "<br/>";
print "subject: $subject \n\n";
print "<br/>";
print "subject_decoded: $subject_decoded \n\n";
[download]

here's what I get via web browser.

subject: Room Rush Enjoy 25% off on your stay. (raw: Room Rush =?utf-8?b?4oCT?= Enjoy 25% off on your stay.) subject_decoded: Room Rush Enjoy 25% off on your stay. (raw: Room Rush – Enjoy 25% off on your stay.)

But, the word " raw: " still appears?

Is this code good? How to enhance it? Anyway, I spent many hours to write the code since I still learn perl

I'm not quite sure how you are getting that output. Here's an SSCCE which you might be able to tailor to your requirements. I've removed all the CGI so you can just run this from the command line.

#!/usr/bin/env perl 
use strict;
use warnings;
use Encode qw(encode decode);

my $subject = "Room Rush \303\242\302\200\302\223 Enjoy 25% off on you
+r stay. (raw: Room Rush =?utf-8?b?4oCT?= Enjoy 25% off on your stay.)
+";

my $decoded = decode ("MIME-Header", $subject);
print encode ("UTF-8", $decoded) . "\n";
[download]

Running this gives:

Room Rush â Enjoy 25% off on your stay. (raw: Room Rush – Enjoy 25% off on your stay.)

which demonstrates that we have successfully decoded the raw part of the header (and encoded it to UTF-8 for output). HTH.

thanks a lot for your wonderful code. I can display some subjects with NON ascii stuffs. But I still can NOT display some.

For e.g - I tried with below 2 subjects. I added below subjects to your code. It will NOT work. I can't think Why? Can You try?

my $subject = "Last Day To Enjoy Extra 15% OFF On Everything For NDB C
+redit Cards (raw: =?utf-8?Q?Last=20Day=20To=20Enjoy=20Extra=2015%=20O
+FF=20On=20Everything=20For=20NDB=20Credit=20Cards)";
[download]

my $subject = "Sing Along and Dance with Desmond De Silva at Pegasus R
+eef Hotel! (raw: =?utf-8?Q?Sing=20Along=20and=20Dance=20with=20Desmon
+d=20De=20Silva=20at=20Pegasus=20Reef=20Hotel=21?)";
[download]

I did below exercise too.

I created a file /tmp/test. contents of /tmp/test

Last Day To Enjoy Extra 15% OFF On Everything For NDB Credit Cards (ra
+w: =?utf-8?Q?Last=20Day=20To=20Enjoy=20Extra=2015%=20OFF=20On=20Every
+thing=20For=20NDB=20Credit=20Cards)
Sing Along and Dance with Desmond De Silva at Pegasus Reef Hotel! (raw
+: =?utf-8?Q?Sing=20Along=20and=20Dance=20with=20Desmond=20De=20Silva=
+20at=20Pegasus=20Reef=20Hotel=21?)
[download]

I ran below command. it also Will NOT work.

# cat /tmp/test | perl -MEncode=decode -ne 'print (decode("MIME-Header
+", "$_"))'

Last Day To Enjoy Extra 15% OFF On Everything For NDB Credit Cards (ra
+w: =?utf-8?Q?Last=20Day=20To=20Enjoy=20Extra=2015%=20OFF=20On=20Every
+thing=20For=20NDB=20Credit=20Cards)
Sing Along and Dance with Desmond De Silva at Pegasus Reef Hotel! (raw
+: =?utf-8?Q?Sing=20Along=20and=20Dance=20with=20Desmond=20De=20Silva=
+20at=20Pegasus=20Reef=20Hotel=21?)
[download]

Any Idea?

Maybe I misunderstand you, but raw: is in the original input string too.