Fence - LISP to pick a pre determined fence line?

[EngME]

I use the "fence" command often inside other commands. I have the need to select a pre-determined line as my "fence" line. Anyone know of a lisp routine (or another way) that I can choose a pre-determined line as my fence line?

THANKS!

[jaberwok]

During which commands?
A line isn't a fence in autocad terminology but you could use a line to provide two pick points.
Some more info might help.

[EngME]

I am using it within the "change to current layer" command.
I am using after I export my Civil 3D surface to 3D faces and before importing it to Navisworks, I need to put the individual faces on their own layers (something Civil 3d can't do yet).
SO it is very time consuming, as I have to update the Navisworks model often. If I could draw a polyline around the areas I want to change (say a road) and re-use this polyline as the fence line everytime I need to do it I would save a lot of time.

[jaberwok]

In acad terms a fence crosses the objects to be selected.
To select with an enclosure you would use BOX, Crossing, Window or one of the Polygon options - which doesn't answer the question, I know.
If you DO have a single line passing through the faces you want to change, the Fast Select express tool (alias = FS) will pick everything that touches the line and LAYCUR will immediately change all of them.
It shouldn't be difficult to combine them into a macro or a lisp.

I hope that helps but I'm not sure that it does but at least it only requires a single pick to select the line.

[EngME]

AWESOME!!
Fast select! Never heard of it! Just what I was looking for. When was that one added? No-one in my office had heard of it... very useful!

Thanks!

[jaberwok]

I'm glad it helped - I learned a bit bit too whilst researching. ;-)