Question

I have two questions regarding an NSArray:

• How can I add nil values to the array? Would be adding [NSNull
null] be correct?
• What would be the best code to
  return the number (count) of nil and non-nil values of this array in
  your view?

Thank you!!

Answer 1

You can’t add nil to an NSArray, so you will have to use [NSNull null] instead as you said.

You can count the number of nil (NSNull) items this way:

NSIndexSet *nilIndexes = [array indexesOfObjectsPassingTest:^BOOL(id obj, NSUInteger idx, BOOL *stop) {
    return obj == [NSNull null];
}];

NSUInteger count = nilIndexes.count;