High memory consumption with Enumerable.Range?

Question

Originally i wanted to know whether ToList allocates more memory than using the constructor of List which takes an IEnumerable

Answer 1

I guess that:

• Enumerable.Range(1, 10000000) only creates an IEnumerable and doesn't create items yet.

• Enumerable.Range(1, 10000000).ToArray() creates an array, using memory for the numbers

• Enumerable.Range(1, 10000000).ToList() creates the numbers and additional data to manage the list (links between parts. The list can change its size and needs to allocate memory in blocks).