字符串中的Javascript递减数

Question

How do I decrement a number in a string? Right now I've got this:

var existingId = "test 10 test";

let newId = existingId .replace(/\d+/g, function(match, number) {
       return parseInt(number)-1;
});

The number is not always in the same place. I cannot store the number in a variable.

But my regex is not correct.

Answer 1

You almost got it

var existingId = "test 10 test";

let newId = existingId.replace(/\d+/g, function(match) {
    return parseInt(match) - 1;
});

Answer 2

use match argument instead number

let newId = existingId.replace(/\d+/g, function (match, number) {
                return parseInt(match) - 1;
);