I'd like to convert a money formatted string into a float in javascript.

ex: '$1,000.20' convert to a float 1000.20

'USD 1,000.20' convert to a float 1000.20

I'm also interested to know how to replace alphabetic characters to say '*'

How can this be implemented?

I'd like to convert a money formatted string into a float in javascript.

ex: '$1,000.20' convert to a float 1000.20

'USD 1,000.20' convert to a float 1000.20

I'm also interested to know how to replace alphabetic characters to say '*'

How can this be implemented?

• javascript

6 Answers 6

You could pick out numbers from an arbitrary string with regex:

var match= string.match(/[0-9,.]*/);
if (match!==null) {
    var amount= parseFloat( match[0].replace(/,/g, '') ); // replace , thousands separator
}

However! It's generally a no-no to store money amounts in a floating point type due to the inaccuracy of floating point calculations. Of course JavaScript only gives you floating-point numbers, but by sticking to whole numbers (eg. of cents) you get accurate calculations up to the odd quadrillion.

Best of all for dealing with money is to use a decimal arithmetic type. This isn't a built-in type in JavaScript, but here's an implementation of it. (It is, unfortunately, rather heavyweight... I'm thinking of hacking up a simpler implementation of just the basics for trivial cases where you only need basic arithmetic.)

I'm also interested to know how to replace alphabetic characters to say '*'

regex again:

string.replace(/[A-Z]/gi, '*')

(for values of “alphabetic characters” within ASCII. If you need non-ASCII Unicode letters to be replaced you'd have to construct a much more involved character class... JavaScript doesn't have built-in classes for the metadata of the whole Unicode character set.)

Long time ago I made an regex to handle all kind of currency ...

([+-]?[0-9|^.|^,]+)[\.|,]([0-9]+)$

Look the result of it

then you just need to get the fraction part, remove all "." and "," and concat with the fraction part if it exists

The final results become:

let currency = "R$ -123.324,123,323"
let regex = /([+-]?[0-9|^.|^,]+)[\.|,]([0-9]+)$/igm
let result = regex.exec(currency);
console.log("Regex result: " + result);
let floatResult = result? result[1].replace(/[.,]/g, "")+ "." + result[2] : currency.replace(/[^0-9-+]/g, "");
console.log("Final result: " + floatResult);

Codepen: https://codepen.io/nicollaas94/pen/zdOevo?editors=0011

Remove all non number symbols:

dirty_string.replace(/[^\d.]/g,'')

this could work:

floatstring=currencystring.replace(/\$/,"");
floatstring=floatstring.replace(/USD/,"");  
floatstring=floatstring.replace(/,/,"");  
floatstring=floatstring*1;

This will remove all chars

      var value = string.replace(',', '');
      value = value.replace(/[^0-9,.]*/, '');
      value = parseFloat(value);

Use JavaScript substring() Method to strip off letters and then parse using parseFloat

parseFloat('1,000.20')

parseFloat('1,000.20')