Creates an empty data buffer of a specified size.
- iOS 7.0+
- macOS 10.9+
- tvOS 9.0+
- watchOS 2.0+
- Xcode 8.0+
The size of the data.
This initializer doesn’t necessarily allocate the requested memory right away.
Data allocates additional memory as needed, so
capacity simply establishes the initial capacity. When it does allocate the initial memory, though, it allocates the specified amount.
This method sets the
count of the data to 0.
If the capacity specified in
capacity is greater than four memory pages in size, this may round the amount of requested memory up to the nearest full page.