convert line to polygon in ArcGIS

Question

How do I convert a non-closed line (think of it as a C) to a polygon filling the area in ArcMap?

I think I can convert a ring to a polygon with the Construct Polygon function on the Advanced Editing Toolbar. However I get the following error: "No polygons were created. Ensure the selected features form continuous rings and overlap the polygons."

Obviously, I need to make my C into an O. It's just a matter of adding a line segment between the two endpoints. How do I add that segment and make the line into a ring?

Answer 1

A manual solution was suggested by Michael Stimson in a comment to the Q:

• Use Feature Vertices to Points (Data Management) to convert the line into a list of points
• Use Points to Line (Data Management) and tick Close Line to get a ring.
• Activate edit mode by clicking Editor > Start editing on the Editor toolbar. Select a target layer that supports polygons. This does not have to be the source layer with your ring (line).
• Select the ring and convert it to a polygon with the Construct Polygon function on the Advanced Editing toolbar.

I accessed the first two functions from the search button which is usually on the right of the screen.