How to add special/non-word character in defined groups?-CodePudding

I have a regex which gives me separate groups of string.

old regex

const regex = /^(.*?)((?:\d{1,3}(?:,\d{1,3})*|\d )(?:\.\d{1,5})?)(\D.*)?$/g;

new regex I wrote but not sure if it's right

const regex = /^(.*?)((?:([^\w\*])|(\d{1,3})(?:,\d{1,3})*|\d )(?:\.\d{1,5})?)(\D.*)?$/g

here is my regex explanation, which primarily I used to have numbers in Group 2 but now that my input range is increasing I want - (non-word character) also to be recognized in it.

But IDK if it is possible to add - in the Group 2.

PS: there won't be any different character other than - or numbers Input are as follows

const inputs= ["$200","$(200)%","100%","$-","$(52,000.5617)%","$30,000","45,444%"];
const regex = /^(.*?)((?:([^\w\*])|(\d{1,3})(?:,\d{1,3})*|\d )(?:\.\d{1,5})?)(\D.*)?$/g;
const text = inputs.match(regex);
let [_, preText = "", number = "", postText = ""] = text;


  1. ^ - start of string (.*?) - Group 1 (preText): any zero or more
    chars other than line break chars, as few as possible

    
  2. ((?:\d{1,3}(?:,\d{1,3})*|\d )(?:\.\d{1,5})?) - Group 2 (number): one
    to three digits followed with zero or more occurrences of a comma
    and one to three digits, or just one or more digits, and then an
    optional sequence of a . and one to five digits
    
  3. (\D.*)? - Group 3 (postText), optional: a non-digit char and then
    any zero or more chars other than line break chars, as many as
    possible $ - end of string.

Output:

this is the output I'm getting from my old regex

[_ = "$(52,000.5617)%", preText = "$", number = "52,000.5617", postText = ")%"]

this is my expected output

[_ = "$-", preText = "$", number = "-", postText = ""]

without preText

[_ = "45,444%", preText = "", number = "45,444", postText = "%"]

CodePudding user response：

You could make the pattern a bit more specific and then allow / disallow what you want to capture.

You could use 3 optional capture groups that do not have overlapping matches, and use a negative lookahead do not match an empty string.

^(?!$)(\$?[^\d\n-]*)(-?(?:\d{1,3}(?:,\d{3})*(?:\.\d{1,5})?|\d )?)([^\d\n]*)$

Explanation

^ Start of string
(?!$) Assert not directly the end of the string
(\$?) Capture group 1, match optional $
[^\d\n-]* Optionally match chars other than a digit, newline or -
( Capture group 2
- -? Match optional -
- (?: Non capture group
  - \d{1,3} Match 1-3 digits
  - (?:,\d{3})* Repeat 1 times , and 3 digits
  - (?:\.\d{1,5})? Match optional . and 1-5 digits
  - | Or
  - \d Match 1 digits
- )? Close the non capture group and make it optional
) Close group 2
([^\d\n]*) Capture group 3, match chars other than a digit or newline

Regex demo

const inputs = ["$200", "$(200)%", "100%", "$-", "$(52,000.5617)%", "$30,000", "45,444%"];
const regex = /^(?!$)(\$?[^\d\n-]*)(-?(?:\d{1,3}(?:,\d{3})*(?:\.\d{1,5})?|\d )?)([^\d\n]*)$/;
inputs.forEach(s => {
  const m = s.match(regex);
  if (m) {
    let [_, preText = "", number = "", postText = ""] = m;
    console.log("input --> "   s);
    console.log("preText --> "   preText);
    console.log("number --> "   number);
    console.log("postText --> "   postText);
    console.log("------------------------------------");
  }
});