Remove Layer Filters - How To

Good Evening Everyone;

I usually post on the ADT customization group but felt this little nugget
would help all of you LISPers out there working with AutoCAD. I am working
on a super purge program for ADT (that completely cleans the drawing and
makes it r14 compatible for a client) and wanted to post this here for
anyone who needs to get rid of those pesky layer filters that just keep
popping up after a while.

This routine has been tested on 2002 only so no garuantees on 2004

(defun PurgeLayerFilters ()
(vl-load-com)
(esp:InitAc)
(if (and (= (vla-get-HasExtensionDictionary (vla-get-layers *AcDoc*))
:vlax-true)
(= (vl-catch-all-error-p
(vl-catch-all-apply 'vla-item
(list
(vla-getextensiondictionary (vla-get-layers *AcDoc*))
"ACAD_LAYERFILTERS")
)
)
)
)
(vlax-for x (vla-item (vla-getextensiondictionary (vla-get-layers
*AcDoc*)) "ACAD_LAYERFILTERS")
(vla-delete x)
)
)
(esp:RelAc)
)

(defun cLF () (PurgeLayerFilters))

The functions esp:InitAc and esp:RelAc are just a couple of automation
routines to set the AutoCAD application, Document and Model Space as global
variables (*AcApp*, *AcDoc* and *AcDocMs*) so you can substitute them as
needed.

If you wish, you can replace the esp:InitAc with (setq AcDoc
(vla-get-activedocument (vlax-get-acad-object))), replace all instances of
*AcDoc* with AcDoc and replace esp:RelAc with (vlax-release-object AcDoc)
and (setq AcDoc nil)

I added a command line access defun cLF so you can access this from the
command line.

Hope this helps anyone who needs it and any comments are welcome.

P.S. Theres no error checking.