/\d+/ matches any string that has 1 or more digits anywhere in it. If you want a string with only digits, you need to anchor the regex: /^\d+$/. Or in your case, match digits followed by a period and "txt": /^\d+\.txt$/

That says "match the start of the string, followed by 1 or more digits, then a period, then txt, then the end of the string.

In reply to Re: regex matching number by Paladin
in thread regex matching number by InfiniteSilence

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