An application sends an EM_SETRECTNP message to set the formatting rectangle of a multiline edit control. The formatting rectangle is the limiting rectangle of the text. The limiting rectangle is independent of the size of the edit control window. When the edit control is first created, the formatting rectangle is the same as the client area of the edit control window. By using the EM_SETRECTNP message, an application can make the formatting rectangle larger or smaller than the edit control window.
The EM_SETRECTNP message is identical to the EM_SETRECT message, except that the edit control window is not redrawn.
This message is processed only by multiline edit controls.
EM_SETRECTNP wParam = 0; // not used; must be zero lParam = (LPARAM) (LPRECT) lprc; // address of new rectangle
This message does not return a value.