how to validate digit in javascript

Question

How to validate these conditions in javacript?

Correct values samples:123 , 123.1, 123.55.

Should 123. (decimal point without decimals) be accepted or rejected? — PM 77-1
– PM 77-1, Commented Apr 9, 2015 at 4:41

Downgoat · Accepted Answer · 2015-04-09 04:46:11Z

1

Use RegExp

/^(\d{3})(\.\d{1,2})?$/.test(number+'');

\d{3}) means any digits, exactly 3 times

(\.\d{1,2})? is more complicated. It means after the three digits, there can be: A decimal, a digit 1-2 times

This accepts both a string and a number

answered Apr 9, 2015 at 4:38

Downgoat

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4 Comments

You don't need to put \d in square brackets.

He said minimum of 3 digits, your RE allows 1 digit.

Why do you need === number+''? .match() returns false if the RE doesn't match.

And shouldn't you have ^ and $ anchors?

Vigneswaran Marimuthu · Accepted Answer · 2015-04-09 04:43:17Z

0

Regex: /^\d{3}(?:.\d{1,2})?$/

var pattern = /^\d{3}(?:.\d{1,2})?$/;
pattern.test(number);

answered Apr 9, 2015 at 4:43

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