A list of updated rectangles that you update in the back buffer for the presented frame. An application must update every single pixel in each rectangle that it reports to the runtime; the application cannot assume that the pixels are saved from the previous frame. For more information about updating dirty rectangles, see Remarks. You can set this member to nullif DirtyRectsCount is 0. An application must not update any pixel outside of the dirty rectangles.

'宣言
 
Public DirtyRectangles As RectL()

public RectL[] DirtyRectangles