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

I'm kind of late to the party, but to answer the question as stated, there's a more intelligent way:

NSInteger index = [@[@"Six", @"Seven", @"Eight", @"Nine"] indexOfObject:cardName];
if (index != NSNotFound) [self setValue: index + 6];

Note that indexOfObject will look for the match using isEqual:, exactly as in the question.

Answer 2

A bit late but for anyone in the future I was able to get this to work for me

#define CASE(str) if ([__s__ isEqualToString:(str)])
#define SWITCH(s) for (NSString *__s__ = (s); ; )
#define DEFAULT

Answer 3

There are other ways to do that, but switch isn't one of them.

If you only have a few strings, as in your example, the code you have is fine. If you have many cases, you could store the strings as keys in a dictionary and look up the corresponding value:

NSDictionary *cases = @{@"Six" : @6,
                        @"Seven" : @7,
                        //...
                       };

NSNumber *value = [cases objectForKey:cardName];
if (value != nil) {
    [self setValue:[value intValue]];
}

Answer 4

BY FAR.. my FAVORITE "ObjC Add-On" is ObjectMatcher

objswitch(someObject)
    objcase(@"one") { // Nesting works.
        objswitch(@"b")
            objcase(@"a") printf("one/a");
            objcase(@"b") printf("one/b");
            endswitch // Any code can go here, including break/continue/return.
    }
    objcase(@"two") printf("It's TWO.");  // Can omit braces.
    objcase(@"three",     // Can have multiple values in one case.
        nil,              // nil can be a "case" value.
        [self self],      // "Case" values don't have to be constants.
        @"tres", @"trois") { printf("It's a THREE."); }
    defaultcase printf("None of the above."); // Optional default must be at end.
endswitch

AND it works with non-strings, TOO... in loops, even!

for (id ifNumericWhatIsIt in @[@99, @0, @"shnitzel"])
    objswitch(ifNumericWhatIsIt)
        objkind(NSNumber)  printf("It's a NUMBER.... "); 
        objswitch([ifNumericWhatIsIt stringValue])
            objcase(@"3")   printf("It's THREE.\n"); 
            objcase(@"99")  printf("It's NINETY-NINE.\n"); 
            defaultcase     printf("some other Number.\n");
       endswitch
    defaultcase printf("It's something else entirely.\n");
endswitch

It's a NUMBER.... It's NINETY-NINE.
It's a NUMBER.... some other Number.
It's something else entirely.

Best of all, there are SO few {...}'s, :'s, and ()'s

Answer 5

I can't Comment on cris's answer on @Cris answer but i would like to say that:

There is an LIMITATION for @cris's method:

typedef enum will not take alphanumeric values

typedef enum
{
  12Ace, 23Two, 23Three, 23Four, F22ive ... Jack, Queen, King

} CardType;

So here is another One:

Link Stack over flow Go to this user answer "user1717750"

Answer 6

For me, a nice easy way:

NSString *theString = @"item3";   // The one we want to switch on
NSArray *items = @[@"item1", @"item2", @"item3"];
int item = [items indexOfObject:theString];
switch (item) {
    case 0:
       // Item 1
       break;
    case 1:
       // Item 2
       break;
    case 2:
       // Item 3
       break;
    default:
       break;
}