How can you reverse traverse through a C# collection?

Question

Is it possible to have a foreach statement that will traverse through a Collections object in reverse order?

If not a foreach statement, is there another way?

Answer 1

You can use a normal for loop backwards, like this:

for (int i = collection.Count - 1; i >= 0 ; i--) {
    var current = collection[i];
    //Do things
}

You can also use LINQ:

foreach(var current in collection.Reverse()) {
    //Do things
}

However, the normal for loop will probably be a little bit faster.

Answer 2

If you're using 3.5, looks like there is a Reverse() method in LINQ That won't iterate through in reverse order, but would reverse the entire list, then you could do your foreach.

Or you could use a simple for statement:

for(int i = list.Count -1; i >= 0; --i)
{
   x = list[i];
}