Field

[maahee]

(defun c:bm ()

  
;code;;;;;;;;

  (setq s (car(entsel)))
  (if s
    (progn

      (setq ar (vlax-ename->vla-object s))
      (setq area (vla-get-Area ar))
      (setq p (getpoint "\nselect point"))

      (entmakex
	(list
	  (cons 0 "MTEXT")
	  (cons 100 "AcDbEntity")
	  (cons 100 "AcDbMText")
	  (cons 10 p)
	  (cons 40 0.3)
	  (cons 71 5)
	  (cons	1
		(strcat	"%<\\AcObjProp.16.2 Object(%<\\_ObjId "
			(itoa (vla-get-objectid ar))
			">%).Area \\f \"%lu2%pr2%ps\">%"
		)

	  )
	  (cons 7 "Standard")
	  (cons 73 1)
	)
      )
    )					; end progn
  )

;code;;;;;;;;


  
)

This part of the code displays the object area as: <\AcObjProp.16.2 Object(%<\_ObjId 2401165245680>%).Area \f "%lu2%pr2%ps" in AutoCAD model space. If you double-click on the text, it will show the object area. (example 100.00)

[Lee Mac]

If you wish to entmake a field, you need to also entmake the FIELD entity within the TEXT entry of the ACAD_FIELD dictionary found within the extension dictionary attached to the entity - this is theoretically possible, but a lot of work and wheel reinvention.

 

Instead, if you either create the MText object using vla-addmtext or convert the MTEXT entity into a VLA object and set the textstring property to a field expression, the CAD platform will automatically parse the field expression and configure the corresponding dictionaries for you.

Edited 3 hours ago by Lee Mac

[Lee Mac]

But if you were curious as to what the entmake route looks like - consider the following thread:

https://www.theswamp.org/index.php?topic=20446

Edited 3 hours ago by Lee Mac