Delete a non-empty folder

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Method FolderItem.Delete() will work on folders only if the folder is empty.

If you want to delete a folder, you must then delete its content first. But if your folder contains subfolders, then you must empty the subfolders and delete them before. And subfolders can also contain subfolders... This is exactly the kind of work for a recursive method, i.e. a method which calls itself.

The following DeleteFolder function looks complex but should take care of any eventualities, such as the possibility of items being added or deleted by other process while the function iterates the folder contents. It also offers an optional mode in which it tries to delete as much as possible (forced delete), even if some items fail to be deleted.

Function DeleteFolder(theFolder as FolderItem, continueIfErrors as Boolean = false) As Integer
  // Returns an error code if it fails, or zero if the folder was deleted successfully
  
  dim returnCode, lastErr, itemCount as integer
  dim files(), dirs() as FolderItem
  
  if theFolder = nil or not theFolder.Exists() then
    return 0
  end
  
  // Collect the folder‘s contents first.
  // This can be faster than collecting them in reverse order and deleting them right away
  // (this is the case with certain file systems that are optimized for forward iteration)
  itemCount = theFolder.Count
  for i as integer = 1 to itemCount
    dim f as FolderItem
    f = theFolder.TrueItem( i )
    if f <> nil then
      if f.Directory then
        dirs.Append f
      else
        files.Append f
      end
    end
  next
  
  // Now delete the files
  for each f as FolderItem in files
    f.Delete
    lastErr = f.LastErrorCode   // Check if an error occurred
    if lastErr <> 0 then
      if continueIfErrors then
        if returnCode = 0 then returnCode = lastErr
      else
        // Return the error code if any. This will cancel the deletion.
        return lastErr
      end
    end if
  next
  
  redim files(-1) // free the memory used by the files array before we enter recursion
  
  // Now delete the directories
  for each f as FolderItem in dirs
    lastErr = DeleteFolder( f, continueIfErrors )
    if lastErr <> 0 then
      if continueIfErrors then
        if returnCode = 0 then returnCode = lastErr
      else
        // Return the error code if any. This will cancel the deletion.
        return lastErr
      end
    end if
  next
  
  if returnCode = 0 then
    // We‘re done without error, so the folder should be empty and we can delete it.
    theFolder.Delete
    returnCode = theFolder.LastErrorCode
    if returnCode = 0 and theFolder.Exists then
      // some unknown reason prevented the folder from being deleted
      returnCode = -1
    end
  end
  
  return returnCode
End Function

[edit] See also

• Delete items from a list - this page explains why an array of FolderItems is created before deleting them.
• Delete a folder - an alternative approach