How to pass an array in by reference to a function in Objective C

Question

Greetings everyone!

I have a function that has an array pointer passed it to modify stuff in an array:

• (void) arrayFunction:(Byte[])targetarray { // do stuff to targetarray }

It's an array of type Byte, but I don't think that I've put the right thing in the round brackets. What should it be instead of (Byte[])? There may be several arrays of different sizes passed to this function

Thanks in advance!

Answer 1

if it's a plain-old array, I would just do this:

(void)arrayFunction:(Byte*)targetarray

Or, to be more "OO-ish", use NSData instead of a byte array:

(void)arrayFunction:(NSData*)targetarray

Answer 2

It looks like you're using the plain C array. Remember that array pointers are simply pointers to the first element in the array. You don't pass the "whole array" as a reference, you'll just pass the pointer at index 0.

If you're passing the array, you should define your parameter as a pointer, Byte*, because that's what it really is when you pass a simple C array.