CODEWITHSUNDEEP
javascriptregex
TIMEX
TIMEX

Reputation: 272084

In Javascript, how do I check if string is only letters+numbers (underscore allowed)?

How do I check that?

I want to allow all A-Za-z0-9 , and underscore. Any other symbol, the function should return false.

Upvotes: 6

Views: 17104

Answers (2)

ioseb
ioseb

Reputation: 16951

I think this is a solution:

function check(input) {
  return /^\w+$/i.test(input);
}

Upvotes: 1

Tikhon Jelvis
Tikhon Jelvis

Reputation: 68152

You can use a regular expression:

function isValid(str) { return /^\w+$/.test(str); }

\w is a character class that represents exactly what you want: [A-Za-z0-9_]. If you want the empty string to return true, change the + to a *.

To help you remember it, the \w is a word character. (It turns out that words have underscores in JavaScript land.)

Upvotes: 15

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