public static void DrawRoundedRectangle(this ID2D1DeviceContext context, D2D1_ROUNDED_RECT roundedRect, ID2D1Brush brush, float strokeWidth, ID2D1StrokeStyle strokeStyle = null) { if (context == null) { throw new ArgumentNullException(nameof(context)); } if (brush == null) { throw new ArgumentNullException(nameof(brush)); } context.DrawRoundedRectangle(ref roundedRect, brush, strokeWidth, strokeStyle); }