Get layer name from selecting point on arc?

Description of what I'm trying to do:

I need to write a lisp routine to insert a block on an arc, but the block needs to be on the same layer as the arc, no matter what the current layer is.

Anyone help with this one?

 

Write your routine using the following:

Go to AutoCAD help, Autolisp section
and read on the following lisp functions:
setvar, getvar and command. These are
the functions you might use in your lisp
routine.

Study the autocad command "insert".

Start writing your routine by following
these guidelines:
1. Save current layer to a variable (clay).
2. Get layer of arc selected (arclayer).
3..Set current layer to arc's layer.
4. Insert your block.
5. Set current layer to original layer (clay).

Test your routine. If it doesn't work, post
your routine in this thread.

 

Also study these additional Autolisp functions:
entget, entsel, assoc, cdr etc.

 

I understand where are you taking this, but that problem I'm have was I need to select a point on the arc and use that point to get the arc layer name and use it to insert the block to. Inserting the block is no problem. I'm having trouble getting the layer name of the arc from the point on the arc I have selected.

 

Why don't you post your code?

Are you using (ssget)? If so, try
entsel so you have your entity and
point where you want to insert your
block.

 

Here is the specific code. Right now this code will not let me select an arc but I can select a line. This is mainly what I'm trying to accomplish. Everything else in the code is fine. I don't know a lot about this stuff, so I get confused quickly..

(defun elec1 ()
(setvar "cmdecho" 0)
(setq e nil)
(setq objs (getvar "osmode") )
(command "osnap" "quick,end,int,nea")
(setq p1 (getpoint "Select location of symbol on wiring: "))
(command "select" p1 "")
(setq e (ssname (ssget "p") 0))
(command "osnap" "")
(setq ;e (car e)
e (entget e)
x1 (cdr (assoc 10 e))
x2 (cdr (assoc 11 e))
ln (cdr (assoc 8 e))
a1 (angle x1 x2)
a2 (angle x2 x1)
a1 (rtd a1)
)
(command "layer" "s" ln "")
)
(defun c:c-w1 ()
(setq ecl (getvar "clayer"))
(setq snm "c-w1")
(elec1)
(command "insert" snm p1 ns "" "nea" pause "-layer" "s" ecl "")
(setvar "osmode" objs)
)

Thanks

 

Here is one way to do it:

Mike

(setq
ent (entsel)
p0 (osnap (cadr ent) "_near")
lname (objectlayername ent)
)

(defun ObjectLayerName( ;Given an entity name, return the layer on which
it resides
ent ;may be an entity name or an entity assoc list
/
)
(cond
((= "ENAME" (type ent))
(cdr (assoc 8 (entget ent)))
)
((and (listp ent) (boundp ent) (assoc 8 ent))
(cdr (assoc 8 ent))
)
(T (alert (strcat "Invalid argument in ObjectLayerName function: "
(vl-prin1-to-string ent))))
)
)

needs to be on the same layer as the arc, no matter what the current layer
is.

 

clutz,
In your post, you show:
(setq ;e (car e)
...
Is there 'really' a ";" after the (setq ?
if so, remove it.

Bob

 

This is some old code that I'm trying to modify. It was in there from before and was working. I removed the ";" and still works the same. Not sure what it was for.

Thanks

 

Clutz,
Oh. I see why it was there, put it back in..
What do you get for variable ln when you grab the arc ?
(prompt (strcat "\nLayer Name= " ln)) should echo it to command line..This way, you can debug (what) layer it is getting.

Bob

 

An Arc doesn't have a dxf group code 11. You are trying to find the
angle with a nil point.

--
Ken Alexander
Acad2004
Windows2000 Prof.

"We can't solve problems by using the same kind
of thinking we used when we created them."
--Albert Einstein

work on arcs. Anyone have an idea on what needs changed so I can use
the above code on an arc. When I select an arc to insert the symbol
on, it display the following error:

 

Thanks for all the info everyone... I figured it out...