Currency validation

Question

Please help with me writing a JavaScript Validation for currency/money field.

So please provide any regular expressions if u have :)

Answer 1

I built my answer from the accepted answer.

var regex = /^[1-9]\d*(((,\d{3}){1})?(\.\d{0,2})?)$/;

^[1-9] The number must start with 1-9
\d* The number can then have any number of any digits
(...)$ look at the next group from the end (...)$
(...)?(...)? Look for two groups optionally. The first is for the comma, the second is for the decimal.
(,\d{3}){1} Look for one occurance of a comma followed by exactly three digits
\.\d{0,2} Look for a decimal followed by zero, one, or two digits.

This regex works off of these rules:

• Valid values are numbers 0-9, comma and decimal point.

• If a customer enters more than one decimal point or more than one comma, the value is invalid and will not be accepted.

• Examples of invalid input values

  • 1.2.3
  • 1,2,4
• Examples of valid input values
  • 1.23
  • 1,000
  • 3967.
  • 23
  • 1.2
  • 999,999.99

An example can be seen here: http://jsfiddle.net/rat141312/Jpxu6/1/

UPDATE

by changing the [1-9] in the regex to [0-9] any number less than 1 can also be validated. Example: 0.42, 007