Question

When converting NSString to constants, I usually use

[@"..." UTF8String];

I was just looking over apple docs on address book programming and i see they use the macro

CFSTR("...");

Out of curiousity, I’m just wondering is there any different between the two?

Answer 1

CFSTR("...") is essentially the Core Foundation equivalent of @"...". In fact, you can do the following:

const char *utf8dots = [(NSString *)CFSTR("...") UTF8String];

And you’ll get the same result as you would with your first line of code.

In theory, CFSTR() creates a constant CFString, while @"" creates a constant NSString. In practice, the two types are interchangeable.

Does that help?