我想用
Email::Stuffer
发送一封简单的电子邮件。正如预期的那样,它将带有非 ASCII 字符的标头编码为“编码字”。但是当我将它们解码回来时(无论是在我的邮件客户端还是在 Perl 中),我得到了不同的文本,并且 MIME::Base64
对相同的文本进行了不同的编码。use strict;
use warnings;
use Email::Stuffer;
use MIME::Base64;
my $text = 'Ümläut';
print "$text in base64: ", encode_base64($text, ''), "\n";
print "and back: ", decode_base64(encode_base64($text)), "\n";
my $stuffer = Email::Stuffer->subject($text);
my $dump = $stuffer->as_string();
print "Mail dump:\n---\n$dump\n---\n";
$dump =~ m{^Subject:\s*=\?UTF-8\?B\?(.+)\?=}m;
my $encoded = $1;
print "in Subject: $encoded\n";
my $decoded = decode_base64($encoded);
print "subject decoded: $decoded\n";
打印:
Ümläut in base64: w5xtbMOkdXQ=
and back: Ümläut
Mail dump:
---
Date: Sat, 7 Oct 2023 16:31:59 -0500
MIME-Version: 1.0
Subject: =?UTF-8?B?w4PCnG1sw4PCpHV0?=
---
in Subject: w4PCnG1sw4PCpHV0
subject decoded: Ãmläut
(外壳上的
echo "Ümläut" | base64
与
MIME::Base64
一致,也打印出w5xtbMOkdXQK)程序源代码为utf8。当我在 use utf8;
之后添加
use warnings;
时,第一个 print
不会打印预期的变音符号,但 Email::Stuffer
按预期工作。�ml�ut in base64: 3G1s5HV0
and back: �ml�ut
Mail dump:
---
Date: Sat, 7 Oct 2023 16:32:50 -0500
MIME-Version: 1.0
Subject: =?UTF-8?B?w5xtbMOkdXQ=?=
---
in Subject: w5xtbMOkdXQ=
subject decoded: Ümläut
这里有什么区别/为什么会发生这种情况?我怎样才能让
MIME::Base64
和
Email::Stuffer
都同意?$text
预计是解码文本,而不是使用 UTF-8 编码的文本。
use strict;
use warnings;
use feature qw( say );
use utf8; # Source code is encoded using UTF-8.
use open ':std', ':encoding(UTF-8)'; # Terminal expects/provides UTF-8.
use Encode qw( decode encode );
use Email::Stuffer qw( );
use MIME::Base64 qw( decode_base64 encode_base64 );
my $text_ucp = 'Ümläut'; # String of Unicode Code Points.
say $text_ucp;
my $text_utf8_base64 = encode_base64( encode( "UTF-8", $text_ucp ), '');
say $text_utf8_base64;
my $text_ucp2 = encode( "UTF-8", decode_base64( $text_utf8_base64 ) );
say $text_ucp2;
my $stuffer = Email::Stuffer->subject( $text_ucp );
say $stuffer->as_string();