Objective-C NSString Reference Types

Question

I have a simple question. If I am declaring NSString (ref type) as shown below:

 NSString *johnsMoney = @\"200\";
    NSString *marysMoney = johnsMoney;

           


        

Answer 1

No. Remember you are dealing with pointers. So when you do

johnsMoney = @"100";

You are setting the johnsMoney pointer to a different memory address which contains the @"100" value. marysMoney still points to the original address with the @"200" value.

Answer 2

NSString is value type. (Immutable).

And there is a concept of sting iterning as well.

NSString *johnsMoney = @"200";
NSString *marysMoney = johnsMoney;
johnsMoney = @"100";

So when you are changing the string of johnsMoney, its now pointing to new memory address. But marysMoney still having old sting (i.e. 200) so pointing to previous address.

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