Question

I am trying to capture the bold part of strings like this:

1. ‘capture a year range at the end of a string 1995-2010‘

2. ‘if there’s no year range just capture the single year 2005‘

3. ‘capture a year/year range followed by a parenthesis, including the parenthesis 2007-2012 (58 months)‘

This regex works for 1 and 2, but I can’t get it to work for 3:

/(\d+([-–— ]\d+( \(\d+ months\))?)?$)/

What am I doing wrong?

Answer 1

Try this regex:

/\d{4}(?:[-–— ]\d{4})?(?:\s*\([^)]+\))?$/gm

This one captures everything in the brackets.
If you need a regex specific to the text “(number) months” in the brackets, then you can use this: \d{4}(?:[-–— ]\d{4})?(?:\s+\(\d+\smonths\))?$

Link to test: RegexPal or RegExr

Sample text:

• capture a year range at the end of a string 1995-2010
• if there’s no year range just capture the single year 2005
• capture a year/year range followed by a parenthesis, including the
  parenthesis 2007-2012 (58 months)
• trying out another example 1990 (23 weeks)
• trying out another example 1995-2002 (x days)
• trying out another example 2050 (blah blah)
• trying out another example 2050—3000
• trying out another example 2050-3000
• trying out another example 2050–3000

And the JavaScript code:

var regex = /\d{4}(?:[-–— ]\d{4})?(?:\s*\([^)]+\))?$/gm; //multiline enabled
var input = "your input string"; 
if(regex.test(input)) {
  var matches = input.match(regex);
  for(var match in matches) {
    alert(matches[match]);
  } 
} else {
  alert("No matches found!");
}