如何打破电子邮件正文中的长 HTML 字符串

Question

我有一个很长的 HTML 字符串作为我的电子邮件正文，我需要插入换行符 ("\n") 以将 HTML 分成几行，因为邮件服务器有排长队的问题。

如何在不破坏 HTML 标签的情况下做到这一点？

我不是在谈论在 HTML 中添加新的换行符 (<br>)，我想在字符串中插入换行符，这样当邮件服务器获取 HTML 逐行不应该达到行长度限制。

例如：

如果我有一个 HTML 字符串：

<head><title>Enter a title, displayed at the top of the window.</title></head><body><h1>Enter the main heading, usually the same as the title.</h1><p>Be <b>bold</b> in stating your key points. Put them in a list: </p></body>

我想插入新的换行符：

<head>\n<title>\nEnter a title, displayed at the top of the window.\n</title>\n</head>\n<body>\n<h1>\nEnter the main heading, usually the same as the title.\n</h1>\n<p>\nBe <b>bold</b> in stating your key points. Put them in a list: \n</p>\n</body>

Answer 1

许多 HTML 电子邮件使用 quoted-printable 编码：

<head><title>Enter a title, displayed at the top of the window.</title></he=
ad><body><h1>Enter the main heading, usually the same as the title.</h1><p>=
Be <b>bold</b> in stating your key points. Put them in a list: </p></body>

在上面的编码中，尾随 = 标记一行的结尾但不会中断它。可以通过相应地连接行来重新组合原始字符串。

幸运的是，无需重新发明轮子。优秀的 Mail gem can do that for you: (and much more, you want to check out multi-part 封邮件）

require 'mail'

mail = Mail.new do
  content_type 'text/html'
  content_transfer_encoding 'quoted_printable'
  body "<head><title>Enter a title, displayed at the top of the window.</title></head><body><h1>Enter the main heading, usually the same as the title.</h1><p>Be <b>bold</b> in stating your key points. Put them in a list: </p></body>"
end

puts mail.to_s

输出：

Date: Wed, 03 Jun 2020 16:44:11 +0200
Message-ID: <5ed7b7...>
Mime-Version: 1.0
Content-Type: text/html;
 charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<head><title>Enter a title, displayed at the top of the window.</title></=
head><body><h1>Enter the main heading, usually the same as the title.</h1=
><p>Be <b>bold</b> in stating your key points. Put them in a list: </p></=
body>=

自从您标记问题后 ruby-on-rails, you might also want to check out Action Mailer。

如何打破电子邮件正文中的长 HTML 字符串

How to break long HTML string in email body

html

ruby

ruby-on-rails

actionmailer