Drawing On Picturebox Vs Drawing On Form?Feb 18, 2012
I need some code to draw a resizable, draggable rectangular cursor (or selection box) on a picturebox. I found some excellent code (albeit rather old) that does just that, but on a form rather than a picturebox. I have tried converting the code - basically moving things to the picturebox events (Paint, MouseDown, MouseMove etc). It nearly works but leaves a trail behind it when you move or resize the cursor. In other words, the selection rectangle is not being erased before being drawn in the new position.
Is there some fundamental difference between drawing graphics on a form and drawing on a picturebox that would cause this behaviour? Something like, when you invalidate a form and cause a redraw it erases what you did last? If not, then I just need to dig a bit further and work out how the cursor is being erased from the previous position.
Here's the original code that works fine on a form:
Private DragRect As New RectangleF(20, 20, 100, 80)
Private Adornments(7) As RectangleF
Private MouseInRect As Boolean = False