This message is sent by Windows to an input procedure associated with a control. Normally, Windows handles all DIRECTION-key and TAB-key input to the control. By responding to the WM_GETDLGCODE message, an application can take control of a particular type of input and process the input itself.
wParam
This parameter is not used.
lParam
This parameter is not used.
The return value is one or more of the following values, indicating which type of input the application processes:
| Value | Meaning |
| DLGC_DEFPUSHBUTTON | Default push button. |
| DLGC_HASSETSEL | EM_SETSEL messages. |
| DLGC_PUSHBUTTON | Push button. |
| DLGC_RADIOBUTTON | Radio button. |
| DLGC_WANTALLKEYS | All keyboard input. |
| DLGC_WANTARROWS | DIRECTION keys. |
| DLGC_WANTCHARS | WM_CHAR messages. |
| DLGC_WANTMESSAGE | All keyboard input (the application passes this message on to control). |
| DLGC_WANTTAB | TAB key. |
The DefWindowProc function returns zero.
Although the DefWindowProc function always returns zero in response to the WM_GETDLGCODE message, the window functions for the predefined control classes return a code appropriate for each class.
The WM_GETDLGCODE message and the returned values are useful only with user-defined dialog controls or standard controls modified by subclassing.