How to disable MFC writing workspace settings to registry?
c++, mfc, registry
Solution
Edit: My original answer was wrong. I have edited the answer.
You can tell MFC to store settings in an `.ini` file instead of the registry. See this previous answer. (Update: That only works if you are not using `CWinAppEx`.)
If you want to prevent MFC from saving some of the state of the menus and toolbars altogether, add the following to your app’s constructor:
m_bSaveState = FALSE;
The `m_bSaveState` member is only defined if your app is derived from `CWinAppEx`.
Alternatively, you can override `CWinAppEx::SaveState` and `CWinAppEx::LoadState`.
To eliminate the `WindowPlacement` registry key, override `CWinAppEx::StoreWindowPlacement`.
You may still get other registry entries being written. A complete solution would involve subclassing `CSettingsStore` and then, in your application, calling `CSettingsStoreSP::SetRuntimeClass`. (See this for more information.) This is fairly difficult because there are a whole bunch of virtual functions you will have to override in your custom `CSettingsStore` class.
Problem
By default, a basic MFC C++ project in Visual Studio 2010 will store all its workspace settings in the HKCU registry hive under a user-configurable key name. This includes last window size/position, ribbon settings, status bar, etc. How can you disable this feature completely so as to not write to the registry at all? I tried not setting `SetRegistryKey()`, which gave me a debug assertion from the framework on first read/write to registry. `SetRegistryKey((LPCTSTR)NULL)` gave the same results. `SetRegistryBase()` seems to have no effect. No other methods in `CWinApp`/`CWinAppEx` seem to help.