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@Anonymous wrote:
Can you use Lisp to Measure a Polyline without having to select it? Something like
Having just drawn the Lpoly
(setq ep enget)
(setq space (getint "\n Enter spacing"))
(command "measure" ep Block "myblock" space "")
AutoCAD seems to insist on making you select the object to measure manually. Its always been a problem for me.....
If you've just drawn it, that first line should be
(setq ep (entlast))
If you want to select it, but not within the Measure command, and have it fed into that, try:
(setq ep (entget))
(setq space (getint "\n Enter spacing"))
(command "measure" (car ep) "Block" "myblock" space "")
Read about what (entget) actually returns to see why.
I would think (getdist) is a better function for the spacing, since it allows other-than-whole-number values that (getint) won't, and you have the option to specify the distance either by typing something or picking two points on-screen.
Kent Cooper, AIA 
@Anonymous wrote:
....
when I run this
(setq ep (entlast))
(setq space (getint "\n Enter spacing"))
(command "measure" (car ep) "Block" "myblock" space "")
I get this.
Select object to measure: ; error: bad argument type: consp <Entity name: 7ffffb0a4c0>
....
Its just the measure command that won't accept ep passed to the select objects command.
I don't want to pause to manually select the pline ... and it may even be difficult to find the last drawn pline. ....
I should changed your 'enget' to (entsel) rather than just adding the t and parentheses to make (entget) [I just ran with the visual of the misspelling of a function name and its not having parentheses, without noticing it was also the wrong function for the purpose], and I should have have suggested reading about (entsel) instead of (entget).
You've mixed together elements of two different suggestions. The (entlast) function returns an entity name; (entsel) returns a list of an entity name and the point at which it was selected. The Measure command is going to require that you give it an entity name. I suggested using (entlast) "If you've just drawn it," because of your prefacing your code with "Having just drawn the Lpoly." That would put the last-drawn entity's name into the 'ep' variable.
I suggested the code that uses (car ep) only "If you want to select it," which I assume would be needed if it's not necessarily the last-drawn entity. That, after using the should-have-said (entsel) rather than (entget), pulls the entity name out of the list that (entsel) returns, to give it to the Measure command. In your code above, where 'ep' is already an entity name as returned by (entlast), Measure would accept just ep rather than (car ep). [That's assuming, of course, that the last entity is something Measure can be applied to.] The error message is because (car) is looking for the first item in a list [that's what 'consp' tests for], and the entity name in 'ep' isn't a list. The 'ep' variable will contain a list if it's set by (entsel) instead, but that requires User selection.
As for your last sentence quoted above, that conflicts with your original post in which you talk about having just drawn it. If it may not be the last thing drawn, then I don't see how you're going to identify it without manually selecting it, unless, for example, it will always be at exactly the same location, or will be the only thing on its Layer, or there's something else about it that can distinguish it from everything else.
Kent Cooper, AIA
Hi rodb,
as a demo, I did add some if's and prompts to show what has failed.
Change myblock, to the correct one...
(vl-load-com)
(defun c:demo (/ ans ent lastpoly pt_lst space)
(if (and (setq lastpoly (entlast))
(setq ent (entget lastpoly))
);; and
(if (= (cdr (assoc 0 ent)) "LWPOLYLINE")
(if (tblsearch "BLOCK" "myblock")
(if (progn (initget 6)
(setq space (getdist "\n Enter spacing: "))
)
(if (>= (vlax-curve-getDistAtParam lastpoly (vlax-curve-getEndParam lastpoly)) space)
(progn
(setq pt_lst (vl-remove-if-not '(lambda (x) (member (car x) '(10))) ent))
(initget "Start End")
(setq ans (getkword "\n Measure polyline, from start or from end [Start End] <exit>: "))
(cond ((and ans
(wcmatch ans "Start")
)
(command "_.measure" (list lastpoly (cdr (car pt_lst))) "_B" "myblock" "_Y" space)
(prompt "\nLast LwPolyline was mesured from the beginning... ")
)
((and ans
(wcmatch ans "End")
)
(command "_.measure" (list lastpoly (cdr (last pt_lst))) "_B" "myblock" "_Y" space)
(prompt "\nLast LwPolyline was mesured from the end... ")
)
(T
(prompt "\n Exiting... ")
)
)
)
(prompt "\n Spacing longer than LwPolyline ... ")
);; if
(prompt "\n User didn't enter spacing... ")
);; if
(prompt "\n Myblock wasn't found in drawing database... ")
);; if
(prompt "\n Last entity is not a LwPolyline... ")
);; if
(prompt "\n This is an empty dwg, there is no last entity... ")
);; if
(princ)
)
Hope this helps,
Henrique
rodb,
your code, works, you'll have to change the 'measure' prompt sequence...
i.e.
(setq ep (entlast)) (setq seglen (getdist "\nSegment length")) (command "measure" ep "Block" "tapemarks" "_Y" seglen)
you'll have to answer to
Align block with object? [Yes/No] <Y>:
with yes ou no, or simply "" ...
My 'demo' was just an attempt to demonstrate that providing to the measure command, a list with a ename and a point, we can force the measure from the end, or from the start, but providing to the measure command only the ename, the comand will measure from start...
And we should always validate the data, before using it as an argument...
Hope this helps,
Henrique
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