Rhino6 Com Interface

Rhino Developer
1

Hello,
We try connect our program to rhino6 via COM interface.
“rs = rhino.GetScriptObject();” is not work.

Error message from visual studio:

Unable to cast object of type 'System.DBNull' to type 'RhinoScript.RhinoScript'

sample code:

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Threading;

using Rhino;
using RhinoScript;

namespace rhinoCOM
{
class Program
{
static void Main()
{
RhinoScript.RhinoScript rs = null;

        // Try creating an instance of Rhino
        dynamic rhino = null;
        try
        {
            //string rhinoId = "Rhino.Application";
            string rhinoId = "Rhino.Interface";
            System.Type type = System.Type.GetTypeFromProgID(rhinoId);
            rhino = System.Activator.CreateInstance(type);
        }
        catch
        {
        }

        if (null == rhino)
        {
            Console.WriteLine("Failed to create Rhino application");
            return;
        }

        // Wait until Rhino is initialized before calling into it
        const int bail_milliseconds = 15 * 1000;
        int time_waiting = 0;
        while (0 == rhino.IsInitialized())
        {
            Thread.Sleep(100);
            time_waiting += 100;
            if (time_waiting > bail_milliseconds)
            {
                Console.WriteLine("Rhino initialization failed");
                return;
            }
        }

        //rhino.Visible = 1;

        // get error here
        rs = rhino.GetScriptObject();

        double[] pt_1 = { 0, 0, 0 };
        double[] pt_2 = { 100, 100, 100 };

        rs.AddLine(pt_1, pt_2);
    }
}

}

We try this code in other computer, it works.
I have no idea why some computer get error.

Thanks

2

The the code that we use is below, and never fails us. If you have problems on one computer, but not on other computers, you may need to re-install Rhino on the problematic machine.

private dynamic _rhino;
public void StartRhino()
{
  // Try creating an instance of Rhino
  try
  {
    const string rhinoId = "Rhino.Application";
    Type type = Type.GetTypeFromProgID(rhinoId);
    _rhino = Activator.CreateInstance(type);

  }
  catch (Exception e)
  {
    Log("Error creating COM instance, {0}", e);
    return;
  }

  if (null == _rhino)
  {
    Log("Failed to create Rhino application");
    return;
  }

  // Wait until Rhino is initialized before calling into it
  const int bailMilliseconds = 15 * 1000;
  int timeWaiting = 0;
  while (0 == _rhino.IsInitialized())
  {
    Thread.Sleep(100);
    timeWaiting += 100;
    if (timeWaiting > bailMilliseconds)
    {
      Console.WriteLine("Rhino initialization timed out: Failed");
      return;
    }
  }
  Logger.Info("RhinoCom Initialisation took {0} ms.", timeWaiting);
  _rhino.Visible = 1;
}
3

Hi, @menno. Thank you for the reply.
I try this code, it works.
But my code also work until “rhino.Visible”.

I try re-install(uninstall and delete registry keys) and test my code, it works!
I delete registry keys by reference to https://wiki.mcneel.com/rhino/5/uninstall

I dont know why, but it works.

Thanks