Here's a little routine to get you started. You must supply the block name of a block already defined in the drawing. It will ask for the user to select a point on the layer to search for point nodes, if any nodes are found it will insert the block at the node location and on the same layer as the node.
So, using your example, if you have a layer called "manhole" that has point nodes on it, and the drawing has a block defined called "manhole", type the following at the command line:
Command: (ins@pt "manhole")
By doing it this way, you can have a number of different buttons to insert different blocks on different layers.
This is by no means a "final" routine, it is provided to give you something to work with. For instance, I only insert the block at a scale of 1 with no rotation. You may want to revise these which are found in this line:
'insertblock (vlax-3d-point inspt) bname 1.0 1.0 1.0 0)
x y z rot
HTH,
Jeff
(defun ins@pt (bname / ss ent lay inspt blk count)
(if (setq ent (entsel (strcat "\nSelect node on layer to insert \"" bname "\""))) (progn (setq lay (cdr (assoc 8 (entget (car ent))))) (if (setq ss (ssget "x" (list '(0 . "POINT")(cons 8 lay)))) (progn (setq count 0) (repeat (sslength ss) (setq ent (vlax-ename->vla-object (ssname ss count)) inspt (vlax-get ent 'coordinates)) (setq blk (vlax-invoke-method (vla-get-modelspace (vla-get-activedocument (vlax-get-acad-object))) 'insertblock (vlax-3d-point inspt) bname 1.0
1.0 1.0 0)
)
(vla-put-layer blk lay)
(setq count (1+ count))
)
)
)
)
)
(if count
(princ (strcat "\nAdded " (itoa count) " instances of \"" bname "\"")) ) (princ)
)
