Question How to find path to one point not on Navmesh?

I want to find path from Point_Start on navmesh ,and to Point_End not on navmesh.
If I use Navmesh.Raycast ,It will stop at first obstacle point ,obviously wrong.
The path I wanted is as below .but I can't get it because the path status of CalculatePath() is Invalid.
Does anyone know how to find path like this?

 

Once you have your navmesh surface baked, you should be able to tell your agent: agent.SetDestination(your destination). This will make the agent go to the point you want and also will avoid any obstacles. Also a new Unity Asset called "Ultimate AI System", which I recently bought. It did all of that for me and didn't require any coding, so you might want to check it out.