Can Objective-C switch on NSString?

Question

Is there a more intelligent way to rewrite this?

if ([cardName isEqualToString:@\"Six\"]) {
    [self setValue:6];
} else if ([cardName isEqualToString:@\"Se         


        

Answer 1

Unfortunately, switch statements can only be used on primitive types. You do have a few options using collections, though.

Probably the best option would be to store each value as an entry in an NSDictionary.

NSDictionary *stringToNumber = [NSDictionary dictionaryWithObjectsAndKeys:
                                              [NSNumber numberWithInt:6],@"Six",
                                              [NSNumber numberWithInt:7],@"Seven",
                                              [NSNumber numberWithInt:8],@"Eight",
                                              [NSNumber numberWithInt:9],@"Nine",
                                              nil];
NSNumber *number = [stringToNumber objectForKey:cardName];
if(number) [self setValue:[number intValue]];

Answer 2

Here is the more intelligent way to write that. It's to use an NSNumberFormatter in the "spell-out style":

NSString *cardName = ...;

NSNumberFormatter *nf = [[NSNumberFormatter alloc] init];
[nf setNumberStyle:NSNumberFormatterSpellOutStyle];
NSNumber *n = [nf numberFromString:[cardName lowercaseString]];
[self setValue:[n intValue]];
[nf release];

Note that the number formatter wants the string to be lowercased, so we have to do that ourselves before passing it in to the formatter.