Converting currency text values (like $1234.56) to float

Question

I have an UITextField where the user enters currency value like $1,234.56. In an iPhone app, how can I convert that value to float?

possible duplicate of [Re-Apply currency formatting to a UITextField on a change event](http://stackoverflow.com/questions/2388448/re-apply-currency-formatting-to-a-uitextfield-on-a-change-event) — PengOne, Sep 10 '11 at 19:31
Do not use a float for money. Either use NSDecimal or an integer multiplied (scaled) by 100. Eventually there will be an arithmetic operation on the value that will cause rounding errors. — zaph, Sep 10 '11 at 19:32
possible duplicate of [String to float in objective c](http://stackoverflow.com/questions/4831188/string-to-float-in-objective-c) or [Convert currency formatted text to double value](http://stackoverflow.com/questions/7343785/how-to-convert-currency-formatted-text-to-double-value-or-nsnumber-value) — jscs, Sep 10 '11 at 21:44

score 0 · Accepted Answer · edited May 23 '17 at 12:29

You want to use an NSNumberFormatter to go back and forth between a value 1234.56 and a string @"$1,234.56".

Apple has a very good Data Formatting Guide to walk you through setting up and using a currency formatter.

In order to integrate this with a UITextField, you will want to use the delegate method

– textField:shouldChangeCharactersInRange:replacementString:

This allows you to validate and update characters as the user types them in. For an example of how to implement this, look at this post: Re-Apply currency formatting to a UITextField on a change event

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