Lisp to select all objects on specified layers

Hi all! I'm trying to create a lisp that, when activated, will automatically select and delete all objects on several layers, ideally that are written into the lisp itself so I don't have to enter anything. Unfortunately, while I can make sense of code with time, I have a very limited understanding of what's out there, and don't know what commands I need to do what I want to do.

I got a decent start with this code:

(defun c:SALL ()
(setq TargetEnt (car (entsel "\nSelect object on layer to select: ")))
(setq TargetLayer (assoc 8 (entget TargetEnt)))
(sssetfirst nil (ssget "_X" (list TargetLayer)))
(princ)
)

taken from

here, but I can't figure out how to have it automatically select items from specified layers, and adding an erase command at the end of the whole thing doesn't seem to work.

If anyone could help me finish this, I would greatly appreciate it!

Welcome to CADTutor.

Here is a very simple form of such a program:

(defun c:delonlayer ( / i s )
   (if (setq s (ssget "_X" '((8 . "[highlight]Layer1,Layer2,Layer3[/highlight]"))))
       (repeat (setq i (sslength s)) (entdel (ssname s (setq i (1- i)))))
   )
   (princ)
)

Perfect! Thanks!

Maybe a command line version ?

(defun delonlayer (lays / i s )
   (if (setq s (ssget "_X" (List (cons 8 lays))))
       (repeat (setq i (sslength s)) (entdel (ssname s (setq i (1- i)))))
   )
   (princ)
)

type this on command line
(delonlayer ""Layer1,Layer2,Layer3")