javascript regex for whole and decimal numbers (money)

Question

Trying to write a javascript regex for forcing users to enter decimal after a whole number, doesn't seem like many people want to do this as my searches have yielded nothing that suits my needs.

Match: 2.00 20.00 200.00 1.73 0.10

No Match: .2 .20 . 1 10 1.0 0.1 1.

Here is what I have currently:

var regexp=/^[0-9]{1,}\\.{1}[0-9]{2}$/;

In plain english, users must enter money in X.XX format. Just a whole number by itself is disallowed.

I'd appreciate any help and also teaching insight anyone has to offer in making this work.

EDIT:

Here is code:

var notempty=/[a-zA-Z0-9\.\$]/g;
var money=/^[0-9]{1,}\.{1}[0-9]{2}$/;

if ( (notempty.test(document.getElementById('numbers').value)) && (!money.test(document.getElementById('numbers').value)) )
{alert('Wrong format');}

Answer 1

Your initial regular expression is correct, the problem is actually your notempty check can short-circuit the condition if the value is false . For example if you have a character which is not a letter, number, dollar sign, or period the /[a-zA-Z0-9\\.\\$]/ it will evaluate false and ignore the item after the && as the values don't matter because false && [any conditions] = false . For example if the input value was "+" :

if ( false && ... )
    // invalid format [the expression was false, so this isn't ran]

Since the first condition is false the entire expression becomes false, leading to a improper "correct format" . The "empty check" isn't needed in this case anyway, you can simply have:

if (money.test(document.getElementById('numbers').value) {
    // valid format
} else {
    // invalid format
}

As noted by @JostCrozier, your expression can be simplified to: /^\\d+\\.\\d{2}$/ , which is functionally equivalent.