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The framework calls this member function when the SetWindowLong function is about to change one or more of the window's styles.

afx_msg void OnStyleChanging( 
   int nStyleType, 
   LPSTYLESTRUCT lpStyleStruct  


Specifies whether the window's extended or nonextended styles have changed. This parameter can be a combination of the following values:

  • GWL_EXSTYLE   The window's extended styles have changed.

  • GWL_STYLE   The window's nonextended styles have changed.


Points to a STYLESTRUCT structure that contains the new styles for the window. An application can examine the styles and change them.


This member function is called by the framework to allow your application to handle a Windows message. The parameters passed to your function reflect the parameters received by the framework when the message was received. If you call the base-class implementation of this function, that implementation will use the parameters originally passed with the message and not the parameters you supply to the function.

Header: afxwin.h