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How to keep CDC* pDC around for life of application?

Currently, I use MFC (SDI application), and I need to refer to CDC* pDC for drawing at many places, however, these are not called from within OnDraw() or OnPaint() (basically I can not pass in CDC), every time I need the DC, I use GetDC() to get a pointer to it. Unfortunally, these calls happen quite a lot, I end up call GetDC() too many time, and this is not efficient, and everytime I call GetDC() it seems to erase what I draw before. My question is:
Is there a way to get DC once and refer to it when needed? It look like the pointer returns from GetDC() is just a temporary pointer, it becomes NULL as soon as I get out of function scope. Thanks,
-Thang

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Answers2000

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plaroche

Answers2000 last remark is very good and that solution should not be used. Programmers should try to stay as friendly as possible with the OS, helping a lot to avoid problems that nobody could foresee.

I think it'd be preferable to create a compatible DC and bitmap as member variables, do the drawing to that dc and in OnDraw or OnPaint call a BitBlt.

This may be a design issue but keeping a dc for such a long time does not seem apropriate.

Answers2000

You can grab a DC for extending period, it's just a bit "naughty".

Guilty Admission: I did infact do this in one my apps (SDK rather MFC style, but to the same effect)

tpnguyen

ASKER

Thank you both Answers2000 & plaroche. It worked ! I will take into consideration of the resouces. Thanks again.