Sorry - I'm trying to understand exactly what you are trying to accomplish. "delete all the files in subfolders using the listbox" doesn't explain things very well...
A listbox is a user interface control, which doesn't do anything except display the contents of the list items stored within the listbox, and allow the user to choose one or more of these items. It will not read a folder, or self populate, or do anything with the data it contains.
Are you attempting to display the contents of a folder, allowing a user to choose one or more of the file names, and then delete these files, or are you attempting to allow the user to select a folder, and then delete all files contained within the folder chosen by the user?
And, if the latter, how do you want to address potential sub-folders (and sub-sub-folders, ad-nauseum, as a directory structure is a tree structure) ?
Do your questions concern getting a directory using the DIR command, deleting the files, or do they fall in the arena of recursion?
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