Question

When I’m using string formatting, can I access one parameter multiple times without passing it again?

Example:

NSString *parameter1 = @"1";
NSString *parameter2 = @"2";

NSString *myString;
myString = [NSString stringWithFormat:@"I want to print parameter1 here: %@, parameter2 here: %@ and now access parameter1 again: %@ _without_ passing it again.",parameter1, parameter2, parameter1];

Is there a way to access the first parameter again without writing “, parameter1” again?

Answer 1

Yes, using positional arguments:

// prints: foo bar foo bar
NSLog(@"%@", [NSString stringWithFormat:@"%2$@ %1$@ %2$@ %1$@", @"bar", @"foo"]);

// NSLog supports it too
NSLog(@"%2$@ %1$@ %2$@ %1$@", @"bar", @"foo");