Entities

Is syntax for Vlisp entities written significantly different than Alisp entities? In the command line I enter the following:

(ssget "x" '((0 . "TEXT")))

The response should be: <SELECTION SET: 1>

I am getting "nil".

What is the difference here? Thank you!

 

This indicats no text entities were found.....

Jeff

entities? In the command line I enter the following:

 

Is syntax for Vlisp entities written significantly different than Alisp
entities?

Lisp is lisp, entities are entities. Vlisp brought a shiny new IDE and
additional ways to do more things, but it didn't change entity data or
render previous lisps inoperable. If the return from the ssget is nil, it
means there wasn't any text found.

Note that there are other text-like things (mtext, attributes, etc.) which
won't be found by this filter.

 

In R2002, with some 'text' out there, I get:

Command: (ssget "x" '((0 . "TEXT")))
<Selection set: 2>

What ver Acad ? Any 'text' out there ?

Bob

 

Found this in Discussion Group, search for 'ssget'..
By Tony Tanzillo.

;; Active Document:
(setq doc (vla-get-ActiveDocument (vlax-get-acad-object)))

(if (ssget "x" <your filter list>)

(progn

(setq ss (vla-get-ActiveSelectionSet doc))

;; Now ss contains the same objects found
;; by the call to (ssget)

;; after you're done, you can release it:

(vlax-release-object ss)
)
)

 

(setq doc (vla-get-ActiveDocument (vlax-get-acad-object)))

I understand that VLA objects offer some advantages over the traditional
data type, and that ActiveX programming can be faster (if the program is
massive enough for speed to matter), and that accessing certain properties
can be "easier" once you've swallowed all the code overhead of
vla-get-this-and-get-that.

But for routine purposes, doesn't all of the above pretty much distill down
to (setq ss (ssget "x" <your filter list>))? I'm wondering, in what kinds of
operations or what kinds of situations would the vla approach be clearly
superior to the older approach?

Conversely, are there situations where doing the vla thing only results in
excess gobbledygook? For instance, I might simply want a count of all blocks
named "foo" and I could get that from (sslength (ssget "x" '((2 . "foo")))).
Is there any benefit in doing the same thing in a more long-winded form?

 

Tom,

Here's an example of vlisp ActiveX which I think is easier than using vanilla LISP
when dealing with selection sets. Of course it assumes someone is equally comfortable
dealing with vla-objects or enames while processing the objects in question.

(setq doc (vla-get-ActiveDocument (vlax-get-acad-object)))
(if (ssget "x" <your filter list>)
(vlax-for item (vlax-get doc 'ActiveSelectionSet)
;;do whatever here like foreach processing a list
)
)

Notice two things. The selection set isn't assigned to a symbol. No (setq ss
(ssget...)). The ActiveSelectionSet property of doc serves that purpose. And there's
no need to step through the selection set with a traditional structure like this:

(setq index 0)
(repeat (sslength ss)
;;do whatever
(setq index (1+ index))
)

If the number of symbols required reflects which method is easier, I think ActiveX
wins.

And if (vlax-get vla-object 'Layer) makes more sense than trying to remember DXF code
8 will return an object's layer name given proper code, well ActiveX wins again.

Regards
Joe Burke