The WM_NCCREATE message is sent prior to the WM_CREATE message when a window is first created.
WM_NCCREATE
lpcs = (LPCREATESTRUCT) lParam; // initialization data
Parameters
lpcs
Value of wParam. Points to the CREATESTRUCT structure for the window.
Return Values
If an application processes this message, it should return TRUE to continue creation of the window. If the application returns FALSE, the CreateWindow or CreateWindowEx function will return a NULL handle.
Default Action
The DefWindowProc function returns TRUE.
See Also
CreateWindow, CreateWindowEx, DefWindowProc, CREATESTRUCT, WM_CREATE