How to target a letter after a dash in Javascript replace using RegEx?

Question

What I have here is a script that changes the value in a textarea via onclick of a button. I do this using Javascript replace together with RegEx. So there's a specified value for every number.

In this sample, however, I couldn't make a letter after a dash to work.

const mapper = new Map();
mapper.set("10th", "11th");
mapper.set("-", "Deleted");

mapper.set("63-51", "40");
mapper.set("121AA", "95");
mapper.set("121-I", "Deleted");
mapper.set("121-OO", "Deleted");

function fixtext() {
  const elm = document.getElementById("textarea1");
  if (elm) {
    elm.value = elm.value
      .replace(
        /\b\d+(?:[A-Z]|([A-Z])\1|d|th|st|nd)?(|\-\d+)?\b/g,
        m => mapper.has(m) ? mapper.get(m) : m
      );
  }
}

<textarea id="textarea1" rows="4" cols="50">121AA will become 95 and 63-51 will become 40. This should be the same for 121-I and 121-OO.</textarea>

<button class="nbtngreen" onclick="fixtext()">Update</button>

So after a click of the button, 121-I should become Deleted as specified. That's also the case for 121-OO.

I'd appreciate any help on how to fix the RegEx I'm using. Many thanks in advance!

Do you also need to match -? Try /\b\d+(?:-?([A-Z])\1?|[rn]d|th|st)?(?:-\d+)?\b|-/i, see the regex demo. — Wiktor Stribiżew
– Wiktor Stribiżew, Commented Jan 18, 2021 at 17:51

Barmar · Accepted Answer · 2021-01-18 18:00:38Z

Your regexp only matches \d+ after -. Change that to [A-Z\d]+ to match letters or digits there.

You don't need an alternative with an empty string inside a group with a ? quantifier, since the quantifier means the other pattern is optional.

[A-Z]|([A-Z])\1 can be simplified to just ([A-Z])\1?.

const mapper = new Map();
mapper.set("10th", "11th");
mapper.set("-", "Deleted");

mapper.set("63-51", "40");
mapper.set("121AA", "95");
mapper.set("121-I", "Deleted");
mapper.set("121-OO", "Deleted");

function fixtext() {
  const elm = document.getElementById("textarea1");
  if (elm) {
    elm.value = elm.value
      .replace(
        /\b\d+(?:([A-Z])\1?|d|th|st|nd)?(-[A-Z\d]+)?\b/g,
        m => mapper.has(m) ? mapper.get(m) : m
      );
  }
}

<textarea id="textarea1" rows="4" cols="50">121AA will become 95 and 63-51 will become 40. This should be the same for 121-I and 121-OO.</textarea>

<button class="nbtngreen" onclick="fixtext()">Update</button>

Collectives™ on Stack Overflow

How to target a letter after a dash in Javascript replace using RegEx?

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related