Test if the planned path is valid/walkable

Sorry if this is a trivial question but I couldn’t find the answer by myself.I schedule a new path at the arrival to target.I want to check if the planned path is valid in terms 1)reachable ,not blocked 2) valid(inside the grid area) .I have seen in the demos path.error is used to indicate if the path is ok.But is there a more detailed query system?

Thanks.

Hi

To be absolutely sure, you have to search for the path to see if it is possible. But a quick check can be done with PathUtilities - A* Pathfinding Project

Should I create GraphNode explicitly or I can retrieve the searched ones somehow?

Found this http://www.arongranberg.com/vanillaforums/discussion/74/target-not-reachable