使用PCRE正则表达式从文本中解析电子邮件标头

I need to parse (split) a text file containing emails exported from Outlook. I am splitting it using preg_split with PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE

我需要解析(拆分)包含从Outlook导出的电子邮件的文本文件。我使用preg_split与PREG_SPLIT_NO_EMPTY |分割它PREG_SPLIT_DELIM_CAPTURE

My goal is to capture message header section with the regular expression, i.e. starting from "From:" line and ending with the blank line before message body.

我的目标是使用正则表达式捕获邮件头部分,即从“From:”行开始,以邮件正文之前的空行结束。

Constraints:

Multilingual field names expected

预期多语言字段名称

Number of header fields varies (CC, BCC, Attachments)

标题字段数量不同(CC,BCC,附件)

Some fields may be on more than one line (To, CC, BCC, Subject, Attachments)

某些字段可能位于多行(To,CC,BCC,Subject,Attachments)

the text file is pre-treated: replace multiple spaces and tabs with single space, replace leading and trailing spaces.

预处理文本文件:用单个空格替换多个空格和制表符,替换前导和尾随空格。

I have been at it whole day, cannot get the last part to work. It does work on [gskinner regex testing page]: http://regexr.com?36v27 , but not in php.

我一整天都在这里,不能让最后一部分工作。它适用于[gskinner regex测试页面]:http://regexr.com?36v27,但不适用于php。

Subject:

From: Black, Jack (LA)
Sent: Monday, October 28, 2013 6:36 PM
To: George, Jackson (London); DCS.CC.DARWIN (Australia)
Cc: Bar, Foo (Istanbul); Ex, Reg (Istanbul); Smith, John (Istanbul); Rambo,
John J. (Gaziantep); Matrix, John (Phuket)
Subject: RE: PREVENTIVE AND CORRECTIVE ACTIONS / FOOBAR

Dear George,

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Thank you and best regards,

Jack B. Black (Mr)
Operations Manager (GGD)
FU Supervisor (R34, R57)

Phone: +1112212212 (local 1111)
Mobile: +12 121.111.11.12

From: George, Jackson (UK)
Sent: Monday, October 28, 2013 5:57 PM
To: DCS.CC.DARWIN (Australia)
Bar, Foo (Istanbul); Ex, Reg (Istanbul); Smith, John (Istanbul); Rambo,
John J. (Gaziantep); Matrix, John (Phuket)
Subject: PREVENTIVE AND CORRECTIVE ACTIONS / FOOBAR

Dear Colleagues,

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Best Regards.

SDFD srfgGD
Field coordinator (GGD)
Customer Representative

sds dfsd sdfgsef sdfsd
sgzdfgdfg fgfg gdfg
Footer text etc
sdfdfdf dfgsdfgsdfgsdfg
Phone : +90 212 368 40 00 (ext:3814)

Regex:

preg_match(
                 '/                         # delimiter
                (                           # capturing group start
                [\ A-Z][a-z]+:.+\(.+\)\R    # From: field
                [A-Z][a-z]+:.+\R            # Sent: fields
                [A-Z][a-z]+:.+\R            # To: field (1st line)
                (?:.+\R)+              # any additional header lines, before blank line (To, CC, BCC, Subject, Attachments)
                )                           # capturing group end
                # delimiter + modifiers /x',$text_clean, $matches);
        echo '<b>Matches: '.count($matches).'</b>';
        print_r($matches);

I am having problem getting additional header lines:

我在获取其他标题行时遇到问题:

(?:.+\R)+              # any additional header lines...

Any help is appreciated

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2 个解决方案

#1

The shortest way is to use preg_match_all with a lazy quantifier:

最简单的方法是使用preg_match_all和一个惰性量词:

preg_match_all('/^From.*?\R\R/ims', $mails, $matches);
print_r($matches);

#2

Thanks everyone for input, however I figured it using my method. A few points are confusing to me, but working solution is further below.

谢谢大家的意见,但我想用它的方法。有几点让我很困惑,但工作解决方案还在下面。

Why preg_match returns first result twice instead of two matches:(http://www.ideone.com/Xj6aaF)1

为什么preg_match返回第一个结果两次而不是两次匹配:(http://www.ideone.com/Xj6aaF)1
(?:.+\R)+ The dot seems to match any character AND NO CHARACTERS, that's why it kept on missing blank lines. I finid that strange - isn't the + supposed to be 1 or more quantifier?

(?:。+ \ R)+点似乎匹配任何字符和没有字符,这就是为什么它保持缺少空白行。我觉得奇怪 - 不是+应该是1个或更多量词?

Anyway, when I changed my regex pattern to (?:\S.+\R)+ it does what I want using preg_split.

无论如何,当我将我的正则表达式模式更改为(?:\ S。+ \ R)+时,它使用preg_split执行我想要的操作。

Demo

Though, technically my problem is solved, I would love someone to explain the above two points.

虽然从技术上讲我的问题已经解决,但我希望有人能够解释以上两点。

#1