Surface and line intersection point.

How to find point at with line intersects with edgesurf. I need to know exact position of the (x,y,z) of this point.
In isometric view after Hide command I see lines and edgesurf intersection, but I cant capture coordinates.
I try to trim line with surface plane, so I could know line endpoint coordinates (as I assume intersection coordinates would be equal to line endpoint values captured with grip tool)
Sorry for my English, hope you understand my problem.
Thaks in advice, Edgar

Command:ID

Problem is that I can't use snap tools to specify precise intersection. this intersection is visible only after HIDE command.
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Oh, sorry. I was making it too easy. Probably you'll have to construct a figure for calculation. Draw a line(s) that you can object snap to. Measure/Divide/List/ID as near as possible and place a node(point) to object snap to.

I have a lisp routine that will yield the "projection" of any point onto any 3d plane. If you set the UCS so that your line is pointing straight "up" (delta Z only), and use the 3D-Projector lisp on my site, it will give you the point where the line would intersect the plane, even if it doesn't. It is designed to be used in the middle of commands, at the "from point" or "to point" prompts.

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any
"to
...and of course the "pick point" prompt.

Thanks for help.