Step 4: Setting the Keyboard Behavior
Before your application can gain access to the keyboard, it must set the device's behavior using the IDirectInputDevice::SetCooperativeLevel method, as shown in Sample Function 1: DI_Init. This method accepts the handle to the window to be associated with the device. DirectInput does not support exclusive access to keyboard devices, so the DISCL_NONEXCLUSIVE flag must be included in the dwFlags parameter.
The following example attempts to set the device's cooperative level. If this fails, it calls the DI_Term application-defined sample function to deallocate existing DirectInput objects, if any.
// Set the cooperative level
hr = g_lpDIDevice->SetCooperativeLevel(g_hwndMain,
DISCL_FOREGROUND | DISCL_NONEXCLUSIVE);
if FAILED(hr){
DI_Term();
return FALSE;
}