How can I get the color of a sketch?

I want to get the color of a sketch but faild.


method 1:


I get the feature of sketch,then I use API of


Feature::GetMaterialPropertyValues.This Method can't work successfuly.


method 2:


I get the sketch segment first.


Then I use the API of SketchSegment::get_Color.


But this API only work under DrawingDoc,


I want to get the color of sketch under a PartDoc.


Anyone can help me?? Thanks a lot!!