Returns a file using its index or its name from the file collection.
Parameters:
iIndex
The index or the name of the file to retrieve from
the collection of files.
As a numerics, this index is the rank of the file
in the collection.
The index of the first file in the collection is 1, and
the index of the last file is Count.
As a string, it is the name you assigned to the file using
the