What could be the reason not to use parenthesis classes in C ++?

Question

Often had to perform the following task: change the state of something, perform an action, and then change the state to the original. For example, in Win32 GDI you need to change the background color, then make a few drawings, and then change the color back.

This can be done directly:

COLORREF oldColor = SetBkColor( deviceContext, newColor );
drawStuff( deviceContext );
SetBkColor( deviceContext, oldColor );

or through a class of brackets that will perform a direct change to the constructor and a reverse change in the destructor:

CBkColorSwitcher switcher( deviceContext, newColor );
drawStuff( deviceContext );
//once control reaches end of block the switcher is destroyed and the change is reverted

The advantage of the cluster class is obvious - if an exception is thrown between the changes, the change is returned correctly. What are the disadvantages?

Answer 1

I'm nitpicking here, but:

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Answer 2

++, RAII. API Win32 - API- C, . ++, RAII, API C ++. Java- RAII finally.

Answer 3

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Answer 4

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