如何在java邮件中的电子邮件主题行中包含£pound符号

Question

如何在通过java邮件发送的电子邮件的主题行中包含英镑符号？

我发送时显示不正确.

Answer 1

主题是标题.标头只使用ascii-7所以要正确编码ascii-7字符,你应该使用正确的编码.

如果您正在使用的类允许您指示某些编码尝试使用UTF-8.

mimeMessage.setSubject(yourSubject, "UTF-8");

如果您手动编写标题,请使用以下任何一个:

MimeUtility.encodeWord(yourSubject, "UTF-8", "B"); // base-64
MimeUtility.encodeWord(yourSubject, "UTF-8", "Q"); // quoted-printable

这或多或少是MimeMessage在setSubject(str,encoding)中的作用:

setHeader("Subject", MimeUtility.fold(9, MimeUtility.encodeText(subject, charset, null)));
// fold splits the value in several lines with no more than 72 chars

样品

我试过这个:

public static void main(String[] args) throws Exception {
            // manual encoding
        System.out.println(MimeUtility.encodeText("How to include £ pound symbol", "UTF-8", "Q"));
        System.out.println(MimeUtility.encodeText("How to include £ pound symbol", "UTF-8", "B"));

            // MimeMessage encoding
        MimeMessage m = new MimeMessage((Session) null);
        m.setSubject("How to include £ pound symbol", "UTF-8");
        m.setContent("lalala", "text/plain");
        m.writeTo(System.out);
    }

输出是:

=?UTF-8?Q?How_to_include_=C2=A3_pound_symbol?=
=?UTF-8?B?SG93IHRvIGluY2x1ZGUgwqMgcG91bmQgc3ltYm9s?=

(......)

Message-ID: <21944831.01314352473121.JavaMail.HAC001ES@SE115179>
Subject: =?UTF-8?Q?How_to_include_=C2=A3_pound_symbol?=
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

lalala

无论如何你总是可以使用:

String yourEncodedString = MimeUtility.encodeText(str, "UTF-8", "Q");
mimeMessage.setHeader("Subject", yourEncodedString);