Deleting Files in Subfolder and delete empty Folders - vb.net

Question

I have to write a PlugIn (in VB.NET) that deletes files after a set amount of days. I've been using this Code to "delete" all files older then DataAge:
For testing purposes I use Log(file.Name) instead of file.Delete().
Dim directory As New IO.DirectoryInfo(.PluginXML.DeleteDirectory) //.PluginXML.DeleteDirectory = FilePath
For Each file As IO.FileInfo In directory.GetFiles()
If (Now - file.CreationTime).Days > .PluginXML.DataAge Then Log(file.Name) //.PluginXML.DataAge = FileAge
Next
How do I check for old files/empty folders in Subfolders from .PluginXML.DeleteDirectory?
I tried something like this, but it would delete the folders, instead of old files.
For Each folder As IO.DirectoryInfo In directory.GetDirectories()
If (Now - folder.CreationTime).Days > .PluginXML.DataAge Then Log(folder.FullName)
Next

Answer 1

One option is to use the overload of GetFiles (or even better*, EnumerateFiles) that accepts a SearchOption with which you can specify that it recurses all directories. For example:
For Each file As FileInfo In directory.EnumerateFiles("*.*", SearchOption.AllDirectories)
If (Now - file.CreationTime).Days > .PluginXML.DataAge Then Log(file.Name)
Next
The alternative is to create a recursive function that walks the directory tree using EnumerateDirectories:
Public Sub ProcessDirectory(directory as DirectoryInfo, dataAge as Integer)
For Each file As FileInfo In directory.EnumerateFiles()
If (Now - file.CreationTime).Days > dataAge Then Log(file.Name)
Next
For Each subDir as DirectoryInfo In directory.EnumerateDirectories()
ProcessDirectory(subDir, dataAge)
Next
End Sub
And then call the method using your base/root path
Dim rootDir As New DirectoryInfo(.PluginXML.DeleteDirectory)
ProcessDirectory(rootDir, .PluginXML.DataAge)
Though note that you will probably need to add error handling for when a directory is inaccessible, such as when an UnauthorizedAccessException or SecurityException is thrown.
* GetFiles loads all files into memory at once whereas EnumerateFiles returns an IEnumerable<FileInfo> that streams the results. This has benefits if you are dealing with directories that contain lots of files, especially if using the AllDirectories option.