From Xojo Documentation

Read-Only Property (As Boolean )
BooleanValue = aFolderItem.Directory

Supported for all project types and targets.

True if the FolderItem is a directory (a folder).


Prompt the user to choose a folder and then display the number of files it contains:

Dim f As FolderItem
f = SelectFolder

If f.Directory Then
MsgBox("The folder has " + Str(f.Count) + " files.")
MsgBox("The folderitem is not a directory!")
End If

This code checks for a specific folder on the drive:

Dim f As FolderItem
f = GetFolderItem("Resources")
If f <> Nil And f.Exists And f.Directory Then
// The folder exists so fetch a file from it
Dim file As FolderItem = f.Child("sample.html")
End If