How can the feild of resizeimg access void render CustomParameterAttributes class?

public class CustomParameterAttributes : Grasshopper.Kernel.Attributes.GH_ComponentAttributes
{
protected override void Render(GH_Canvas canvas, Graphics graphics, GH_CanvasChannel channel)
{
}
}

public class imagesampelerComponent : GH_Component
 {
   protected  override  void SolveInstance(IGH_DataAccess DA)
   {
       Bitmap img = "null";
       DA.GetData(0,ref img);
       bitmap resizeimg=img.resize();
   }

}