I have problem writing a conditional regex. I need to find multiline text with an optional end. Usually it is the "normal end", sometimes I have this additional suffix.

Could some one please support me with this problem.

Here is my example:

Start of Text
 some thing in between
 some thing in between
 some thing in between
Normal end of text
Optional suffix


^(?:Start)[\d\w\s]*?(?(?=Optional.*)Optional.*|Normal.*)

It only matches until "Normal end of text" Even though, the "Optional" is present. What I understood from contional regex, it should find "Optional" and though match "Optional"

Thank you so much.

CodePudding user response：

You can use

^(Start)((?s:.*?))(Normal.*)(\s*Optional.*)?

See the regex demo. Details:

• ^ - start of string
• (Start) - Group 1: Start
• ((?s:.*?)) - Group 2: any zero or more chars as few as possible
• (Normal.*) - Group 3: Normal and then any zero or more chars other than line break chars as few as possible
• (\s*Optional.*)? - an optional Group 4 matching zero or more whitespaces, Optional and then any zero or more chars other than line break chars as few as possible.