Regex allow only 0-9 and the - character, and dot (.)

Question

I Need a regex to validate 0-9 and allow . and - characters.

Following is working for 0-9 and . characters:

Regex invalidCharsRegex = new Regex(@"^*[0-9\.]+$");

`bool _result - Regex.Ismatch("YourString", @"^[0-9\-.]+$")` — John Woo, Sep 08 '13 at 19:41
You can find answer here. http://stackoverflow.com/questions/5570820/regex-allow-digits-and-a-single-dot — Irfan TahirKheli, Sep 08 '13 at 19:41

score 7 · Accepted Answer · answered Sep 08 '13 at 19:42

Your regex is weird...

Regex invalidCharsRegex = new Regex(@"^*[0-9\.]+$");

Remove the first asterisk, it's not doing anything good.

And to allow - characters, you simply add it to the character class. Also, you don't need to escape the dot in a character class:

Regex invalidCharsRegex = new Regex(@"^[0-9.-]+$");

If you're trying to validate a number, this regex will have to be revised, because the regex will accept ---- or ...... Something a bit like this for integer/floating numbers:

Regex invalidCharsRegex = new Regex(@"^\-?[0-9]+(?:\.[0-9]+)?$");

score 0 · Answer 2 · answered Sep 08 '13 at 19:43

0

Regex invalidCharsRegex = new Regex(@"(?<=^| )\d+(\.\d+)?(?=$| )|(?<=^| )\.\d+(?=$| )");

This will allow numbers like 1, 1.2, .1 etc

answered Sep 08 '13 at 19:43

Irfan TahirKheli

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Regex allow only 0-9 and the - character, and dot (.)

2 Answers2