我想编写一个正则表达式，从电子邮件MIME消息字符串（eml）中捕获编码单词部分。 例如，这是电子邮件的一部分：
<div dir=3D"ltr"><br clear=3D"all"><div><div dir=3D"ltr"><div style=3D"dire=
ction:rtl">-------------</div><div style=3D"direction:rtl">=D7=91=D7=91=D7=
=A8=D7=9B=D7=94,</div><div style=3D"direction:rtl">=D7=90=D7=91=D7=99=D7=A2=
=D7=93 =D7=9B=D7=94=D7=9F</div></div></div>
</div>
--20cf3003bc2e044e980500f755dc--
--20cf3003bc2e044e9d0500f755de
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--20cf3003bc2e044e9d0500f755de--
我只想抓住这部分：
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我无法用正则表达式做到这一点，所以我尝试使用以下行，该行始终以"--"开头并以"--"结尾。 请注意，在所需部件之前始终有一个空行。我试过："（\s）.*（--）$"，但它只返回以下行。
有人可以帮忙吗？
听起来您正在尝试解析多部分/混合电子邮件。已经有大多数语言的库可以做到这一点。如果你想写你自己的，我建议遵循多部分消息的结构。
- 查找内容类型标头中定义的边界
- 将消息拆分为由边界分隔的部分（前缀为 --）。
- 对于每个部分，请查找表示标头末尾的两个连续换行符的第一个实例。
虽然正则表达式可能对此有所帮助。我不确定它是解析结构化消息的正确工具。
您可以使用此正则表达式：
ns*nK(?:[^-]{2})*.?(?=n--)
在线演示