topic Entity-list to search for layer in Visual LISP, AutoLISP and General Customization Forum

Entity-list to search for layer

Anonymous — Thu, 23 Mar 2017 15:28:57 GMT

I'm trying to get the layer of the last entity inserted in the drawing (not the current layer) and from what I understood, I need to use entget and entlast (in LISP), but I was told that Entity-List is not used to do this, and I became even more confused . Could someone help me with this problem, how to do what I need without using entity-list?

Re: Entity-list to search for layer

john.uhden — Thu, 23 Mar 2017 15:42:06 GMT

When you say "entity-list" do you mean "entget?" What's wrong with your using entget? Unless maybe you have an affection for vla-objects.

Re: Entity-list to search for layer

Anonymous — Thu, 23 Mar 2017 16:03:57 GMT

Yes, I referred to entget. And how do I save more than one entity in the case of more than one drawing? Would I have to put the values I get with entget into a list?

Re: Entity-list to search for layer

john.uhden — Thu, 23 Mar 2017 16:36:43 GMT

Computers are so fast these days that most of the time it's just as fast to extract the data anew rather than storing it in some other location. Besides, entity names change from drawing to drawing and session to session. BTW, the values returned by entget are in a list with dxf codes for each of the items so that you can snag exactly what property for which you are looking.

So, to answer your question...

(setq layer (cdr (assoc 8 (entget (entlast)))))

Now if there is some entity that you need to reference in the future, then you can get into using handles (cdr (assoc 5 (entget ...))), but where and how to store and retrieve the handle values is rather an advanced subject.

Re: Entity-list to search for layer

Kent1Cooper — Thu, 23 Mar 2017 16:40:44 GMT

To get the Layer of the last thing drawn:

(cdr (assoc 8 (entget (entlast))))

You used the phrase "last entity inserted," and if by that you meant actually INSERTed [the last Block], rather than the last thing [of any kind] created in any way, that would be a different challenge.

You mention "more than one drawing." That's not going to be possible with AutoLisp, at least not in a single list. An AutoLisp routine can't work in more than one drawing at a time. If you really want to "save more than one entity" from more than one drawing, I think you would need to do something like WBLOCK them out, and INSERT the resulting external drawings into some common drawing afterwards. If you really mean to save more than one [back to the beginning of Post 1] Layer name from the last entities in several drawings, those could be written out to a text file of some kind, and they could be added into the same text file from multiple drawings. Entity names can't be handled that way -- they may look like text, but they're not string objects, so even if they can be written out to a file in a textual form, when retrieved from it they would only be text strings, and would no longer have their entity name meaning. Besides, however unlikely, the same entity name [or even the same handle as @john.uhden mentions] could occur in different drawings, representing different entities. And the same entity can even have a different entity name [but never a different handle] when you close and get back into a drawing.

Re: Entity-list to search for layer

Anonymous — Thu, 23 Mar 2017 17:33:24 GMT

Maybe it would help us know what are you trying to do with that layer...

As john and kent said, you can get the layer of last created object using

(SETQ layer (CDR (ASSOC 8 (ENTGET (ENTLAST)))))

I have learned that kind of stuff with a book (PDF) but its written in spanish. I attach it in case you can use it.