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iOS Objective-C Basics (Retired) Foundation Framework NSString

stringByAppendingString

Hey,

Just wondering about the stringByAppendingString method. The code from the lesson is as follows:

    NSString *alfa = @"alfa";
    NSString *delta = @"delta";
    NSLog(@"%@ %@", alfa, delta);

    NSString *concat = [[alfa stringByAppendingString:delta] stringByAppendingString:@"lotsmore"];

    NSLog(@"%@", concat);

How come you don't need to declare *lotsmore and initialise it?

Cheers

P.S. By the by, writing 'My favorite color is purple' is like nails against a blackboard for an Australian!

1 Answer

Heidi Brebels
Heidi Brebels
21,620 Points

You're not using "lotsmore" here as a variable, but as a value. Probably because it's not needed as a variable. Why would you declare something a variable if you don't need it more than once or if the value is likely to change often?

It's probably also not a variable here just to show you that you can use a variable and an actual value interchangeable.

You can declare it a variable:

NSString *lotsmore = @"lotsmore";

NSString *concat = [[alfa stringByAppendingString:delta] stringByAppendingString:lotsmore];

But at the same time, you can declare nothing a variable:

NSString *concat = [[@"alfa" stringByAppendingString:@"delta"] stringByAppendingString:@"lotsmore"];