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javascriptregexsubstringspecial-characterscapture-group

JS Regex- find a substring contains special characters

Can you please help me to understand how to do the following?

I'm having a strings (3 formats for this string):

  1. "Section_1: hello & goodbye | section_2: kuku"
  2. "Section_1: hello & goodbye & hola | section_2: kuku"
  3. "Section_1: hello | section_2: kuku"

I want the get the result:

  1. Group section_1: "hello & goodbye", Group section_2: "kuku"
  2. Group section_1: "hello & goodbye & hola", Group section_2: "kuku"
  3. Group section_1: "hello", Group section_2: "kuku"

Now I have the regex (but it's not working for me because of the '&'):

Section_1:\s*(?<section_1>\w+)(\s*\|\s*(Section_2:(\s*(?<section_2>.*))?)?)?

Note: the regex is capturing 2 groups- "section_1" and "section_2"

The question is- how can I read sub string the can contains zero or more from " & {word}"

Thanks in advance

Solution

  • As per the comments we established that the ' & '- combination acts as a delimiter between words. There are probably a ton of ways to write a pattern to capture these substrings, but to me these can be grouped into extensive or simple. Depending if you need to validate the input more thoroughly you could use:

    ^section_1:\s*(?<section_1>[a-z]+(?:\s&\s[a-z]+)*)\s*\|\s*section_2:\s*(?<section_2>[a-z]+(?:\s&\s[a-z]+)*)$

    See an online demo. The pattern means:

    • ^ - Start-line anchor;
    • section_1:\s* - Match 'Section_1:' literally followed by 0+ whitespace characters;
    • (?<section_1>[a-z]+(?:\s+&\s[a-z]+)*) - A named capture group to catch [a-z]+ as 1+ upper/lower letters (case-insensitive flag), followed by a nested non-capture group matching 0+ times the pattern (?:\s&\s[a-z]+)* to test for any delimiter as per above followed by another word;
    • \s*\|\s*section_2:\s* - Match whitespace characters, a literal pipe-symbol and literally 'Section_2:' upto;
    • (?<section_2>[a-z]+(?:\s&\s[a-z]+)*) - A 2nd named capture group to match the same pattern as the above named capture group;
    • $ - End-line anchor.

    Note: As mentioned, there are a ton of differnt pattern one could use depending on how specific you need to be about validating input. For example: \s*(?<section_1>[^:|]+?)\s*\|\s*[^:]*:\s*(?<section_2>.+) may also work.