Sort DirectoryInfo by creation date

Question

This code gives me the a list of folders. Without sorting it comes up oldest first. Although I don't think that could be guaranteed.(it could sort based on file name which is a date). I want to use the OrderBy or OrderByDescending function to sort it newest first based on the creation date.

Dim di As New DirectoryInfo(root)
folderList = di.GetDirectories()

'does not work
folderList.OrderByDescending(Function(x) x.CreationTime)

Thank you

Answer 1

You need to (re)assign the value that OrderByDescending returns to the variable, it will not order the original collection.

For example:

folderList = folderList.
    OrderByDescending(Function(x) x.CreationTime).
    ToArray()

Another option is to sort the original array:

Array.Sort(folderList, Function(d1, d2) d1.CreationTime.CompareTo(d2.CreationTime))

I'm using this overload of Array.Sort with a Comparison(Of T) .