NSNumberFormatter currency negative number - foundation

Question

My current code is
NSNumberFormatter *f = [[[NSNumberFormatter alloc] init] autorelease];
[f setNumberStyle:NSNumberFormatterCurrencyStyle];
[f setCurrencySymbol:NSLocalizedString(#"CURRENCY", #"Get Currency")];
NSString * stringCurrecy = [f stringFromNumber:(-70.00)];
I'm using NSLog to check the string currency and it's printing "($ 70.00)".
I changed "(", ")" symbol. How can I achieve this:
( $ 70.00 ) -> - $70.00 or $ -70.00

Answer 1

You have to set the negative format.
Add this line:
[f setNegativeFormat:#"-¤#,##0.00"];
but maybe you just want to set the locale with [f setLocale:] instead of setting every format option on your own.
(and next time post code that does compile.)

Answer 2

I have a NSNumber category that does this:
#implementation NSNumber (Formatter)
- (NSString *)currencyStringValue
{
NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.locale = [NSLocale currentLocale];
formatter.numberStyle = NSNumberFormatterCurrencyStyle;
formatter.negativePrefix = [NSString stringWithFormat:#"- %#", formatter.currencySymbol];
formatter.negativeSuffix = #"";
return [formatter stringFromNumber:self];
}
#end

Answer 3

Setting negativeFormat to "-" almost worked for me, but it was dropping off the currency symbol. At least for en_US locale, this fits my needs:
NSLocale *US = [NSLocale localeWithLocaleIdentifier:#"en_US"];
NSNumberFormatter *currencyFormatter = [[NSNumberFormatter alloc] init];
[currencyFormatter setNumberStyle:NSNumberFormatterCurrencyStyle];
[currencyFormatter setCurrencyCode:currencyCode];
[currencyFormatter setLocale:priceLocale];
//manually add - prefix to positive format...
NSString *negFormat = [NSString stringWithFormat:#"-%#",currencyFormatter.positiveFormat];
[currencyFormatter setNegativeFormat:negFormat];
I'm not sure whether this is appropriate for all locales, but it works for en_US.