Javascript question regarding the use of regex

Question

I need to find a regex expression for a number 1 to 9, followed by trailing zeroes, followed by the end number 1 to 9. As like in a minesweeper game for clearing zeroes.

How do I match the part of an array where like i have 10009 or 2003 ? ,1to9 then zeroes, then 1to9? How would I write it?

does this work? updated: how do I ask this regex or another regex? the one i have below or a (trailing zeroes and 1-9)

(^[1-9][0+][1-9]$) 

Answer 1

[1-9][0]+[1-9]

Move the + outside of the square brackets. Otherwise, it will match the literal character.

 const regex = new RegExp("[1-9][0]+[1-9]") function test(testCase){ console.log(regex.test(testCase)) } test("10009") test("2003")

To make the first digit optional, you can do:

[1-9]?[0]+[1-9]

 const regex = new RegExp("[1-9]?[0]+[1-9]") function test(testCase){ console.log(regex.test(testCase)) } test("0009") test("2003")

Answer 2

When you say [0+] then you are saying that select any of either 0 or +

you want is quantifier 0+ which means 0 one or more times

You can use ^[1-9]0+[1-9]$

 const regex = /^[1-9]0+[1-9]$/; function test(str) { return regex.test(str); } console.log(test("10009")); console.log(test("2003"));