Objective-C Switch Statement

Question

Possible Duplicate:
Declaring variables inside a switch statement

I'm having difficulty getting XCode to let me write a particular switch statement in Objective-C. I'm famiiar with the syntax and could rewrite it as if/else blocks but I'm curious.

switch (textField.tag) {
        case kComment:
            ingredient.comment = textField.text;
            break;
        case kQuantity:
            NSLog(@""); // removing this line causes a compiler error           
            NSNumberFormatter *fmt = [[NSNumberFormatter alloc] init];
            fmt.generatesDecimalNumbers = true;
            NSNumber *quantity = [fmt numberFromString:textField.text];
            [fmt release]; 
            ingredient.quantity = quantity;
            break;
    }

I can't see the syntax error, it's as though I need to trick the compiler into allowing this.

score 15 · Accepted Answer · answered Dec 22 '11 at 14:57

15

You can not add variable declaration after the label. You can add a semicolon instead of call to NSLog() for instance. Or declare variable before the switch. Or add another {}.

answered Dec 22 '11 at 14:57

Michael Krelin - hacker

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The easiest way is to put semicolon after between case and declaration . – Ariel Dec 22 '11 at 15:08
Yes, it is sure the least number of keystrokes, but depending on the context the most esthetically pleasing solution may differ :) – Michael Krelin - hacker Dec 22 '11 at 15:09
That's why I've up-voted your answer :) – Ariel Dec 22 '11 at 15:13
Here is where I say: Thank you ;-) – Michael Krelin - hacker Dec 22 '11 at 15:13
Interesting, thanks for the tip. Braces are probably aesthetically best. – Echilon Dec 22 '11 at 15:19
@Echilon, I'm often of the same opinion. – Michael Krelin - hacker Dec 22 '11 at 15:35

score -2 · Answer 2 · edited Dec 23 '11 at 02:16

-2

Remove the variable declaration part within the switch statement.

Within switch statement you can't create any variable in Objective-C.

NSNumberFormatter *fmt = nil;
NSNumber *quantity = nil;
switch (textField.tag) {
        case kComment:
            ingredient.comment = textField.text;
            break;
        case kQuantity:
            fmt = [[NSNumberFormatter alloc] init];
            fmt.generatesDecimalNumbers = true;
            quantity = [fmt numberFromString:textField.text];
            [fmt release]; 
            ingredient.quantity = quantity;
            break; 
    }

Try this...

edited Dec 23 '11 at 02:16

markhunte

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answered Dec 22 '11 at 15:19

iCreative

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It appears you can -- and I don't see why not. on the second line in a switch statement, declaration works. Even if the first line is just ';' – Jhong May 07 '12 at 16:12

Objective-C Switch Statement

2 Answers2