I've looked around for a while now and can't seem to find any documentation that covers my concern.
I am wondering if I should ever be concerned with the order a range supplied to List<T>.AddRange() is added to the collection. I can assume all day that it will be added in the sequential order I supplied; that is, if I supply 0, 8, 5, 2, 9 it shouldn't ever be added in the order of 9, 5, 2, 0, 8 or anything other than 0, 8, 5, 2, 9.
I've ran a test in a console application to determine the results using a post-increment in the AddRange method like so:
List<int> test = new List<int>();
for (int i = 0; i < 30;)
test.AddRange(new int[] { i++, i++, i++ });
foreach (int i in test)
Console.WriteLine(i);
This prints in sequential order as I expected it to from zero to 29. However, my concern is that I'm unable to find documentation that shows me exactly how this range is added to the collection. I would assume that it would be something along the lines of:
foreach (int i in range)
collection.Add(i);
Which would definitely preserve any order I've supplied, but I would like to ensure that this is actually what is occurring, or at least that what is occurring will never reorder the supplied range.
Apparently I haven't had enough coffee yet today and missed it while looking over the documentation for AddRange. Thank you all anyways, at least it's a great question for future readers that may be curious.
The order of the elements in the collection is preserved in the List.
It's the first line under the section Remarks at: https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic.list-1.addrange?view=netframework-4.7.2