HI,
>> I need a lisp which can draw line between 2 line <<
from AutoCAD 2017 and later versions you will be able to do that and without lisps. by using CENTERLINES command you can create an associative centerline by selecting two line segments.you can learn more by following this link . >> Click <<
Regards,
You may be able to use Bisector.lsp with its BI command, available here. It accepts selection of just about anything straight -- Lines, Xlines, Rays, Polyline line segments, Mlines, Dimension extension lines or linear dimension lines, edges of 3D Faces or 2D Solids or straight edges of 3D Solids, Viewports or Tolerance boxes or assorted other things, as well as such things nested in Blocks or Xrefs. If the two selected objects or sub-objects are parallel, it draw an Xline also parallel and halfway between them; if they're not, it draws one that bisects the angle between them.