Question

我有一堆电子邮件档案，看起来像下面的模式。我正在尝试将以From:开头并以模式From:结尾的电子邮件分开。

From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.


From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: New Greetings
Date: 04/05/1990 10:30 PM

Yet another test email

使用awk，awk '/From/{p=1} p; /Date/{exit}' text.txt。它给出了：

From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

如何修改awk命令以获取：

From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.

提前致谢

Answer 1

对于您当前的输入，应用以下GNU awk 表达式就足够了：

Html.RenderAction("index", "Questions");

输出：

awk -v RS="\n\n\n+" 'NR==1{ print; exit }' file

Answer 2

如果您对新行字符不感兴趣，那么

$ awk '/^From:/{count++} count==1' infile 

$ awk -v mail_no=1 '/^From:/{count++}count==mail_no; count>mail_no{exit}' infile

示例：

$ awk '/^From:/{count++} count==1' infile 
From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.


$ awk '/^From:/{count++} count==2' infile 
From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: New Greetings
Date: 04/05/1990 10:30 PM

Yet another test email

要删除尾随的换行符，我更喜欢使用tac，如下所示

$ awk -v mail_no=1 '/^From:/{count++}count==mail_no;count>mail_no{exit} ' infile | tac | awk 'NF{found=1}found' | tac
From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.

输入：

$ cat infile
From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.


From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: New Greetings
Date: 04/05/1990 10:30 PM

Yet another test email


From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: New Greetings
Date: 04/05/1990 10:30 PM

Yet another test email

Answer 3

找到解决方案

这将从数据中提取所有电子邮件

String[] separated = data.split("From:");
separated[0];
separated[1]; ......

Pattern p = Pattern.compile("\\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\\.[A-Z]{2,4}\\b",Pattern.CASE_INSENSITIVE);
ArrayList<String> emails = new ArrayList<String>();
ArrayList<ArrayList<String>> buchEmails = new ArrayList<ArrayList<String>>();
for(int i=0;i<seperated.length();i++){   
  Matcher matcher = p.matcher(seperated[i]);
    while(matcher.find()) {
      emails.add(matcher.group());
    }
   buchEmails.add(i,emails);
}

Answer 4

如果@veekram在其中一条评论中说明了下一条＆＃34;来自：＆＃34;是分隔符，然后是：

 x = [None]*10

会做的。

Answer 5

为什么不使用旨在解析像`formail这样的电子邮件的程序？例如，要提取第一条消息：

<in.mbox formail -1 -f -ds

输出：

From: Bikram Suwal veekram@gmail.com
To: John Doe johndoe@gmail.com
Subject: Greetings
Date: 04/05/1990 10:30 PM

Hello.
World
This is a test email.

在匹配模式之间打印行块

5 个答案: