C# How can I acquire the name of a plane inside an extrude?

Hello!

I am trying to acquire the name of the plane used inside of an Extrude via C#. This extrude uses an end condition of a reference plane the user picks. I have spent the better part of yesterday researching this - but either I am missing something very simple, or I don't know enough about the API to get what I want from it

I am using GetEndConditionReference Method of ExtrudeFeatureData

So far I have sucessfully created the ExtrudeFeatreData object and called GetDefinion - this allows access to the object that contains GetEndConditionReference (which I think I need to use)

swFeat = (Feature)swSelMgr.GetSelectedObject6(1, -1);  // worksswExtrudeFeatData = (ExtrudeFeatureData2)swFeat.GetDefinition(); // worksendCondition = (object)swExtrudeFeatData.GetEndConditionReference(true, out ECRType); // works (kind of)Debug.Print("testing" + ECRType);  //returns 5 (which is correct and type of Refplane)

endCondition is null though - and I was expecting this to contain on object representing something I could pull the name out of.

I tried to cast this as an object and a refPlane with no success. I guess my first question would be, am I going about this the wrong way?  and Second - what I am I doing wrong to keep getting a null on my endCondition variable.

thanks!

SolidworksApi macros