Child-window controls notify the parent window of events by using a WM_COMMAND message. The wParam parameter of the WM_COMMAND message identifies the control that generated the message.
To recognize an out-of-memory notification from the edit control, add the following code to the WM_COMMAND case:
case IDC_EDIT:
if(HIWORD (lParam) == EN_ERRSPACE) {
MessageBox (
GetFocus (),
“Out of memory.”,
“EditCntl Sample Application”,
MB_ICONHAND | MB_OK
);
}
break;