Filtering a specific Layer with vlax-map-collection and wcmatch

[Herr_Manu]

Hi everyone

i'm Emmanuel and i've been writting (with a lot of help of this forum and all you guys) autolisp and vlisp for over a year and this is the first time i'm officially posting a question in here, so i'm quite excited

 

I'm currently working on in a little routine to filter layers with a specific name, in this case "WIRKFLÄCHE" (german for design area).

and i was using a ssget '((8. "*wirkf*")) but giving that i'm going to use another ssget to modified some objects later, i decided to use vlax-map-collection, and it works fine, but when i'm trying to use (if (wcmatch layername "*WIRKFLÄCHE")) it doesn't filter a thing

 

 

(defun c:layertest (/ acadDoc modelSpace theLayers dwgName layerList)
  
  (vl-load-com)

  (setq
    acadDoc    (vla-get-ActiveDocument (vlax-get-acad-object))
    modelSpace (vla-get-ModelSpace acadDoc)
  )

  (setq theLayers (vla-get-layers acadDoc))
(setq layerList '())

	(vlax-map-collection theLayers
 
  '(lambda (theLayer)
 
    (setq dwgName (vlax-get-property theLayer 'Name))

    (if
      (wcmatch dwgName "*WIRKFLÄCHE")
 	(progn
	    (setq layerList (append (list dwgName) layerList))
	    (setq layerList (reverse layerList))
    	);progn

      );end IF
 
    
 
;;;    (vlax-put-property theLayer "LayerOn" ':vlax-true)
;;; 
;;;    (vla-put-color thelayer 5)
 
  );lambda
 
);vlax-map-collection

);defun

am i missing something in here?

 

 

[rkmcswain]

I just took an existing drawing, created a layer named "WIRKFLÄCHE", ran your code and layerlist does equal 

 

[Tharwat]

Hi,

You need to match the case of the string to get it working with wcmatch function.

(wcmatch (strcase layername) "*WIRKFLÄCHE")

 

[Herr_Manu]

Thanks for the comments, but i think now i'm having some other problems.

 

When i run this function as a whole, i doesn't work, but if i do it by little pieces, it does. some times i get an error like bad argument type: stringp nil    

and some other times i get the error: no function definition: VL-LOAD-COM ... is my computer messing up with me?? 

 

Any idea what can be cause of this errors??? 

[Tharwat]

You may have something wrong with your AutoCAD that might missing one or more .dll file(s) but anyway try it with this little mods.

(defun c:layertest (/ acadDoc modelSpace theLayers dwgName layerList)
  (setq
    acadDoc    (vla-get-ActiveDocument (vlax-get-acad-object))
    modelSpace (vla-get-ModelSpace acadDoc)
    theLayers  (vla-get-layers acadDoc)
  )
  (vlax-map-collection
    theLayers
    '(lambda (theLayer)
       (setq dwgName (vlax-get-property theLayer 'Name))
       (if
         (wcmatch dwgName "*WIRKFLÄCHE")
          (setq layerList (cons dwgName layerList))
       )
     )
  )
  layerList
)
(vl-load-com)

 

[Herr_Manu]

On 10/10/2021 at 5:19 PM, Tharwat said:

You may have something wrong with your AutoCAD that might missing one or more .dll file(s) but anyway try it with this little mods.

(defun c:layertest (/ acadDoc modelSpace theLayers dwgName layerList)
  (setq
    acadDoc    (vla-get-ActiveDocument (vlax-get-acad-object))
    modelSpace (vla-get-ModelSpace acadDoc)
    theLayers  (vla-get-layers acadDoc)
  )
  (vlax-map-collection
    theLayers
    '(lambda (theLayer)
       (setq dwgName (vlax-get-property theLayer 'Name))
       (if
         (wcmatch dwgName "*WIRKFLÄCHE")
          (setq layerList (cons dwgName layerList))
       )
     )
  )
  layerList
)
(vl-load-com)

 

 

Works great! i already managed to make it work. but your version is easier to read. i'm still figuring out, what does exactly mean to use (cons item list) instead of (append). I'm gladly surprised that my approach wasn't that wrong

 

Thanks again for the help

 

 

[Tharwat]

Append function requires an empty list or a list of elements to append item(s) to it but the cons function does not and it is straight forward.