[This is preliminary documentation and subject to change.]
Rich Edit 2.0 and later: Send an EM_STOPGROUPTYPING message to a rich edit control to stop the control from collecting additional typing actions into the current undo action. The control stores the next typing action, if any, into a new action in the undo queue.
Rich Edit 1.0: This message is not supported.
EM_GETUNDONAME
wParam = 0; // not used; must be zero
lParam = 0 ; // not used; must be zero
The parameters are not used; they must be zero.
The return value is zero. The message cannot fail.
A rich edit control groups consecutive typing actions, including characters deleted by using the backspace key, into a single undo action until one of the following events occurs:
You can send the EM_STOPGROUPTYPING message to break consecutive typing actions into smaller undo groups. For example, you could send EM_STOPGROUPTYPING after each character or at each word break.
Windows NT: Requires version 4.0 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in richedit.h.
Rich Edit Controls Overview, Rich Edit Messages, EM_UNDO