function Prototypes:LONG GetWindowLong (HWND hwnd,int nIndex) Parameters:hWnd: Specifies the handle of the windowNIndex: Types of information to be obtainedvalue Function The nindex values are as follows:Gwl_exstyle to get extended window stylegwl_style Get window styleGwl_wndproc Gets the address of the window callback function, or the handle. The CallWindowProc function must be used to invoke theGwl_hinstance getting a handle to an application running instanceGwl_hwndparent Get the handle of the parent windowgwl_id Get the identifier of the windowGwl_userdata Gets the 32-bit value associated with the window (each window has a 32-bit value that is intentionally left to the application that created the window) the following values can be used when the HWND identifies a dialog boxValue ActionDwl_dlgproc Gets the address of the dialog box callback function, or handle. The CallWindowProc function must be used to invoke theDwl_msgresult Get the return value of the message processing in the dialog box callback functionDwl_user Get additional application-private information, such as some handles and pointers, etc. return Value:when successful, returns a 32-bit value for a requestOn failure, return 0, you can use GetLastError to get the error message
Form: GetWindowLong ()
