CLOSELINE is a new feature that is used to immediately mark unclosed endpoints among selected lines, polylines or arcs, and close them conveniently.
Method of automatically closing:
When the selected lines or polylines are parallel to each other, usually they cannot be closed, but if they are two parallel line objects, they can be closed with an arc.
When the selected lines or polylines are not parallel to each other, they can be closed according to the position and the order they are clicked. Sometimes they need to be extended to intersect each other, and segments outside the closing point will be trimmed.
Object types that can be selected and closed include:
Line > Line
Line > Polyline
Line > Arc
Polyline > Polyline
If you have selected an object and it is not marked with a red circle, then it can’t be closed and the “The line segment you selected was invalid. Please select it again” prompt in the command line.
Check CLOSELINE feature in action: