How can I check if a string contains only numbers, comma and periods with regex in javascript?

Question

I have an input field that I will only accept numbers, commas and periods. How can I test if the string is valid according to these rules?

I have tried the following:

var isValid = /([0-9][,][.])$/.test(str);

but it's not working. isValid variable is always false.

i don't but on keypress event we can restricted this symbols — Dinesh, Feb 20 '14 at 12:15
I'm not familiar with javascript, but that regex says: one 0-9, followed by one "," and one ".", end of line. You probably want /([0-9,.]+)$/.test(str); — Unknown, Feb 20 '14 at 12:16

score 28 · Accepted Answer · answered Feb 20 '14 at 12:17

28

Your regexp expects one character from the first class (0-9), then one from the second class (comma) then one from the last class (dot). Instead you want any number of characters (*) from the class containing digits, commas and dots ([0-9,.]). Also, you don't need the parenthesis:

var isValid = /^[0-9,.]*$/.test(str);

DEMO (and explanation): http://regex101.com/r/yK6oF4

answered Feb 20 '14 at 12:17

Tibos

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Thanks, I will mark this an answer as soon as I can. Just a question. How do I add blank spaces to the allowed characters? would it be [0-9,. ]? (Notice the space after period) – Weblurk Feb 20 '14 at 12:29
@Weblurk Yes. You can use the tool i linked to try stuff out. The explanation of the regexp is most useful. – Tibos Feb 20 '14 at 12:44

score 0 · Answer 2 · edited Aug 04 '22 at 13:20

0

var regex = "[-+]?[0-9]*\.?[0-9]*"

This works perfect for decimal number & Integer. e.g.

1 - true
1.1 - true
1.1.1 - false
1.a - false

edited Aug 04 '22 at 13:20

RavinderSingh13

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answered Aug 09 '16 at 16:38

Justin Patel

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How can I check if a string contains only numbers, comma and periods with regex in javascript?

2 Answers2

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