How to get NSLocale from currency code?

I am trying this:

NSDictionary *components = [NSDictionary dictionaryWithObject:@"USD" forKey:NSLocaleCurrencyCode];
NSString *localeIdentifier = [NSLocale localeIdentifierFromComponents:components];
NSLocale *localeForDefaultCurrency = [[NSLocale alloc] initWithLocaleIdentifier:localeIdentifier];

It creates NSLocale object but it does`t contain any regional information. For example,

[localeForDefaultCurrency objectForKey:NSLocaleCountryCode];

returns nil;

Any idea how to开发者_如何学运维 get NSLocale from currency code?

As posted by some Guest in pastebin:

NSDictionary *components = [NSDictionary dictionaryWithObject:@"USD" forKey:NSLocaleCurrencyCode];
NSString *localeIdentifier = [NSLocale localeIdentifierFromComponents:components];
NSLocale *localeForDefaultCurrency = [[NSLocale alloc] initWithLocaleIdentifier:localeIdentifier];

[localeForDefaultCurrency objectForKey:NSLocaleCountryCode];

    NSDictionary *localeInfo = @{NSLocaleCurrencyCode: currencyCode, NSLocaleLanguageCode: [[NSLocale preferredLanguages] objectAtIndex:0]};

    NSLocale *locale = [[NSLocale alloc] initWithLocaleIdentifier:
                        [NSLocale localeIdentifierFromComponents:localeInfo]];

There are tricks like creating locale with id but instead of normal locale id like "en_US" pass it currency code "USD", "EUR", etc., It seems to work for eur and usd in a way I could check it but this is wrong way IMHO.

The only right way I know is to get all locales and then in loop check their currency codes to compare with one you have. This way you will stop the loop when you find your code.

- (NSLocale *) findLocaleByCurrencyCode:(NSString *)_currencyCode
{
        NSArray *locales = [NSLocale availableLocaleIdentifiers];
        NSLocale *locale = nil;
        NSString *localeId;

        for (localeId in locales) {
                locale = [[[NSLocale alloc] initWithLocaleIdentifier:localeId] autorelease];
                NSString *code = [locale objectForKey:NSLocaleCurrencyCode];
                if ([code isEqualToString:_currencyCode])
                        break;
                else
                        locale = nil;
        }

        /* For some codes that locale cannot be found, init it different way. */
        if (locale == nil) {
                NSDictionary *components = [NSDictionary dictionaryWithObject:_currencyCode
                                                                       forKey:NSLocaleCurrencyCode];

                localeId = [NSLocale localeIdentifierFromComponents:components];
                locale = [[NSLocale alloc] initWithLocaleIdentifier:localeId];
        }
        return locale;
}

You can use the power of extensions in Swift:

extension NSLocale {

    static func currencySymbolFromCode(code: String) -> String? {
       let localeIdentifier = NSLocale.localeIdentifierFromComponents([NSLocaleCurrencyCode : code])
       let locale = NSLocale(localeIdentifier: localeIdentifier)
       return locale.objectForKey(NSLocaleCurrencySymbol) as? String
    }

}

In this way, anywhere in your code:

let code = "EUR"
let price = 10
if let currencySymbol = NSLocale.currencySymbolFromCode(code) as? String {
    print("You have to pay \(price)\(currencySymbol)")
}