Capturing all text between delimiters only when there is a line feed

Question

I am trying to capture the text between 2 delimiters only when there is also a line feed within the delimiters. So for example if we have the following text.

Organisation Name <<me.company.name>>
ABN/ACN <<me.company.abn>>
Contact Name <<me.name>>
<<me.PhoneNumber

Another line>>
Email <<me.emailAddress>>

I am wanting to only return the <<me.PhoneNumber \n\n 'Another Line>>

the \n could be anywhere - basically only matches that have at least one \n within the << >> and ignore all other << >>

The pattern I have so far is <<(.?\n)*?>> but this captures all << >> (I'm using C#)

here is an example of what I have tried https://regex101.com/r/sb0wCs/1

Thanks so much for your help

Answer 1

You can use

<<((?:(?!<<|>>).)*?\n(?s:.)*?)>>

See the regex demo. Details:

• << - a << string
• ((?:(?!<<|>>).)*?\n(?s:.)*?) - Group 1:
  • (?:(?!<<|>>).)*? - any zero or more chars (other than newline chars) that do not start >> or << char sequence, as few as possible
  • \n - a LF char
  • (?s:.)*? - any zero or more chars (including newline chars), as few as possible
• >> - a >> string