How to test if a string contains a number with regular expression in javascript?

Question

I'm trying with

function hasANumber(value) {
    return /^.*[0-9]*.*$/.test(value);
}

Where I was wrong?

if you want just to check whether string has at least one digit - /[0-9]+/ — Iłya Bursov
– Iłya Bursov, Commented Feb 26, 2015 at 0:45

Ortiga · Accepted Answer · 2015-02-26 00:50:14Z

1

* in regex means zero or more

You should have used + which means one or more, as in:

/^.*[0-9]+.*$/

Although this can be simplified to:

/[0-9]+/

answered Feb 26, 2015 at 0:50

Ortiga

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Comments

Avinash Raj · Accepted Answer · 2015-02-26 00:54:34Z

1

Just \d would be enough for this case.

> /\d/.test('foo')
false
> /\d/.test('fo1o')
true

[0-9]* in your regex matches a digit zero or more times, so it would allow also the strings which won't have a digit.

answered Feb 26, 2015 at 0:54

Avinash Raj

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Enrique Quero · Accepted Answer · 2015-02-26 00:53:16Z

0

This is the correct form to write the number regex is :

 \d+$

answered Feb 26, 2015 at 0:53

Enrique Quero

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