正则表达式在 javascript 中的某物之间查找字符串

Question

I have this two strings:

(username~contains~'ren'~and~status~contains~false)
(status~contains~false~and~username~contains~'ren')

i need one regex that find what is the status value after contains~

I try something like:

/(?<=status~contains~).*?(?=[)])|(?<=status~contains~).*?(?=~)/gi

pass in exemple 1: (username~contains~'ren'~and~status~contains~false)
fail in exemple 2: (status~contains~false~and~username~contains~'ren' )

I need only the return true or false, but in the second exemple i get false~and~username~contains~'ren'

Answer 1

True or false /^(?=.*status~contains~(true|false)).*/
Use the multi-line option and group 1 is the value.

https://regex101.com/r/N41U56/1

Answer 2

The thing that you could change is to match either a ~ or )

(?<=status~contains~).*?(?=[)~])

Regex demo

Instead of using a lookbehind (which is not yet fully supported across browsers), you could also use a capturing group instead and make sure there are opening and closing parenthesis.

The value is in group 1.

\((?:[^~\r\n]+~)*status~contains~([^~\n]+)(?=[^()]*\)) 

• \( Match an opening (
• (?: Non capturing group
  • [^~\r\n]+~ Match 1+ times any char except ~ or a newline
• )* Close goup, repeat 0+ times
• status~contains~ Match literally
• ( Capture group 1
  • [^~\n]+ Match 1+ times any char except ~ or a newline
• ) Close group
• (?=[^()]*\)) Positive lookahead, assert a closing )

Regex demo

 const regex = /\((?:[^~\r\n]+~)*status~contains~([^~\n]+)(?=[^()]*\))/g; const str = `(username~contains~'ren'~and~status~contains~false) (status~contains~false~and~username~contains~'ren')`; let m; while ((m = regex.exec(str)).== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex;lastIndex++. } console;log(m[1]); }

Answer 3

Try this regex:

/(?<=status~contains)~([^~)]+)[~)]/

and get group 1 from result.

Answer 4

/(?<=status~contains~)[^~)]+(?=[~)])/g

This uses a lookbehind of: status~contains~ and a lookahead of either ~ or ) . Therefore we can match 1 or more characters that are neither ~ nor ) between the lookbehind and lookahead. This is simpler and more efficient than using .*?.

 let re = /(?<=status~contains~)[^~)]+(?=[~)])/g; let text = "(username~contains~'ren'~and~status~contains~false)" + "(status~contains~false~and~username~contains~'ren')"; let m; while (m = re.exec(text)) console.log(m[0]);

See Regex Demo