Using NSScanner to separate string into NSArray by comma

Question

Does anyone know how i can use NSScanner to separate a string by comma into an array EXCEPT when a comma is embedded within quotes?

Before i had been using:

  NSArray *arrData = [strData componentsSeparatedByString:@","];

However i have quotes inside the string that have commas inside them, i want these not to be separated. I have never worked with NSScanner before and i am struggling to come to terms with the documentation. Has anyone done a similar thing before?

Answer 1

If you absolutely have to use an NSScanner you could do something like this.

        NSScanner *scanner = [[NSScanner alloc] initWithString:@"\"Foo, Inc\",0.00,1.00,\"+1.5%\",\"+0.2%\",\"Foo"];
        NSCharacterSet *characters = [NSCharacterSet characterSetWithCharactersInString:@"\","];
        [scanner setCharactersToBeSkipped:nil];
        NSMutableArray *words = [[NSMutableArray alloc]init];
        NSMutableString *word = [[NSMutableString alloc] init];
        BOOL inQuotes = NO;
        while(scanner.isAtEnd == NO)
        {
            NSString *subString;
            [scanner scanUpToCharactersFromSet:characters intoString:&subString];
            NSUInteger currentLocation = [scanner scanLocation];
            if(currentLocation >= scanner.string.length)
            {
                if(subString.length > 0)
                    [words addObject:subString];
                break;
            }
            if([scanner.string characterAtIndex:currentLocation] == '"')
            {
                inQuotes = !inQuotes;
                if(subString == nil)
                {
                    [scanner setScanLocation:currentLocation + 1];
                    continue;
                }
                [word appendFormat:@"%@",subString];
                if(word.length > 0)
                   [words addObject:word.copy];
                [word deleteCharactersInRange:NSMakeRange(0, word.length)];
            }
            if([scanner.string characterAtIndex:currentLocation] == ',')
            {
                if(subString == nil)
                {
                    [scanner setScanLocation:currentLocation + 1];
                    continue;
                }
                if(inQuotes == NO)
                    [words addObject:subString];
                else
                    [word appendFormat:@"%@,",subString];
            }
            [scanner setScanLocation:currentLocation + 1];
        }

EDIT: This gives the following output:

Foo, Inc

0.00

1.00

+1.5%

+0.2%

Foo

Hope this is what you want

As you can see it gets complicated and very error prone, I would recommend using Regex for this.