Question

Note To Self; This part of the string should not be changed because it contains note to self and NTS
Note To Self ; This part of the string should not be changed because it contains note to self and NTS
Note To Self : This part of the string should not be changed because it contains note to self and NTS
Note To Self: This part of the string should not be changed because it contains note to self and NTS
Note To Self - This part of the string should not be changed because it contains note to self and NTS
Note To Self- This part of the string should not be changed because it contains note to self and NTS
Note To Self This part of the string should not be changed because it contains note to self and NTS
NTS ; This part of the string should not be changed because it contains note to self and NTS
NTS; This part of the string should not be changed because it contains note to self and NTS
NTS : This part of the string should not be changed because it contains note to self and NTS
NTS: This part of the string should not be changed because it contains note to self and NTS
NTS- This part of the string should not be changed because it contains note to self and NTS
NTS - This part of the string should not be changed because it contains note to self and NTS
NTS This part of the string should not be changed because it contains note to self and NTS
This part of the string should not be changed because it contains note to self and NTS #NTS

Above is the text I am using to test my regex.

I am using this with PHP, and am just trying to extract the string without the prefix.

Essentially, what I am looking for is extracting this string ‘This part of the string should not be changed because it contains note to self and NTS’ from the given prefixes.

Your help is much appreciated, thanks!

EDIT: by request info was changed.

http://regexr.com?2u3jn

Answer 1

To remove all instances of Note to self or NTS if they are at the start of the line, optionally followed by whitespace and/or punctuation, and to remove #NTS if it’s at the end of a line, you can search for

(^(Note to self|NTS)\W*|#NTS$)

and replace with nothing.

Explanation in the form of a PHP code snippet:

$result = preg_replace(
    '/(             # Either match...
     ^              #  start of line, followed by...
     (              #   either...
      Note to self  #   Note to self
     |              #   or
      NTS           #   NTS
     )              #  followed by...
     \W*            #  any number of non-alphanumeric characters
    |               # or
     \#NTS          #  match #NTS
     $              #  if it\'s the last thing before the end of the line
    )               # End of the alternation.
    /x', 
    '', $subject);