To make is zoomable and scrollable,
PictureBox is your enemy. It won't help at all, only will eat up your development time, performance and resources. It's purpose is mostly static image, maybe reloadable/replaceable — that's it.
This is what you should use instead (see my solution):
How do I clear a panel from old drawing[
^].
Don't tell me that you won't be able to save the image in file if you use this way. You can, and even better then with
PictureBox. If you still in doubt, ask a question; I'll answer.
[EDIT]
But Forms is generally a bad UI library for such things. If you switch to WPF, you virtually won't need to program anything about zooming, panning, even rendering — everything is already done. You simply add objects to
Canvas. You can put all in
ViewBox which will zoom automatically. A lot of benefits.
—SA
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