Function prototype: LONG GetWindowLong (hwnd hwnd,int nIndex) Parameter: hwnd: Specifies the handle of the window NIndex: The type value of the information that needs to be obtained NIndex value is as follows: Gwl_exstyl E gets the extended window style gwl_style gets the window style gwl_wndproc gets the address of the window callback function, or the handle. You must use the CallWindowProc function to call gwl_hinstance to get the handle of the application run instance Gwl_hwndparent get the handle of the parent window gwl_id get the window identifier Gwl_userdata get and window phase The associated 32-bit value (each window has a 32-bit value that is intentionally left to the application that created the window) when the HWND identifies a dialog box, the following value can be used to get the address, or handle, of the dialog box callback function Dwl_dlgproc. You must use the CallWindowProc function to call Dwl_msgresult to get the return value of the message processing procedure in the dialog callback function Dwl_user get additional application private information, such as some handle and pointer return value: When successful, Returns 0 when a requested 32-bit value fails, and you can use GetLastError to get the error message
GetWindowLong ()
