Which is better? array, ArrayList or List (in terms of performance and speed)

Question

I require a fast speed in processing my page. The count of the values to be added will be dynamic.

Which one of the above is preferred? Support with a valid reason.<

Answer 1

List should generally be preferred over ArrayList

• faster for value types as it avoids boxing.
• strongly typed elements

If you want lists you expose to callers to be immutable, this is supported by both List and ArrayList:

List.AsReadOnly()
ArrayList.ReadOnly(ArrayList list);

Your question asks about choosing between ArrayList and List, but your example shows an array, which is neither.