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JavaScript Regular Expressions in JavaScript Reformatting User Input A Better Telephone Number Validator

John Nguyen
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John Nguyen
Full Stack JavaScript Techdegree Graduate 30,501 Points

\D allows for non-digit characters, meaning a-z would be allowed.

If that's the case, how we work around this?

I can think of the 2 things.. 1) Use a stricter regexp 2) restrict input to digits, spaces, and dashes (doesn't sound like a good practice) 3) other?

1 Answer

Umidjon Khaitov
Umidjon Khaitov
8,884 Points

Good question! I think it is obvious that no one writes letters in telephone number input, maybe that's why Joel used \D