Can you pass the entries of a strut array to a int array? if so how?

Question

typedef struct {
  uint8_t  pitch;
}LearnNote;

#define  MAX_NOTE  500

LearnNote  Noteseq[MAX_NOTE]; 

int learnindex=0;
void loop() {
 MIDI.read();
}

void MyHandleNoteOn(byte channel, byte pitch, byte velocity){
Noteseq[learnindex].pitch=pitch;
learnindex++;
}

Answer 1

Its not very clear what you are asking, but I think you are saying can you do this

uint8_t anArray[MAX_NOTE];
anArray = Noteseq.pitch;

In general the answer is no. However in this specific case off the top of my head I think you probably can (maybe). You have a struct which only contains bytes. The compiler will probably pack the sequentially so you will effectively have a contiguous sequence of bytes which you would be able to copy to the byte array by doing:

memcpy (anArray, Noteseq, MAX_NOTE);  // THIS IS BAD PRACTICE!

You can only do this in this case because the types are both 8bit numbers. Its not a good idea to do this copy between an array of structs and a POD type array is just asking for trouble.

Instead use a function to do it.

int* CopyPitch (LearnNote* source, int* destination, int count)
{
    for (int i = 0; i < count; ++i)
    {
        destination[i] = source[i].pitch;
    }
}

(You should really check for null pointers and stuff, but its just an example)