MLM_RESETUNDO

This message resets the undo state to indicate that no undo operations are possible.

Syntax

param1
ULONG ulReserved; /* Reserved value, should be 0. */

param2
ULONG ulReserved; /* Reserved value, should be 0. */

Parameters

ulReserved (ULONG) - input

Reserved value, should be 0.

ulReserved (ULONG) - input

Reserved value, should be 0.

Returns

usOperation (USHORT) - return

Operation that can be undone or redone.

0: An undo or redo operation is not possible.

WM_CHAR: A WM_CHAR message, or messages for a simple string of keystrokes, can

be undone or redone.

MLM_SETFONT: A MLM_SETFONT message can be undone or redone.

MLM_SETTEXTCOLOR: A MLM_SETTEXTCOLOR message can be undone or redone for both

background and foreground color.

MLM_CUT: A MLM_CUT message can be undone or redone.

MLM_PASTE: A MLM_PASTE message can be undone or redone.

MLM_CLEAR: A MLM_CLEAR message can be undone or redone.

rc (BOOL) - return

Undo or redo indicator.

TRUE: An undo is possible.

FALSE: A redo is possible.

Remarks

This message resets the undo state of the MLE to indicate that the last operation cannot be undone (null return from MLM_QUERYUNDO). This can be used by the application when it performs an operation that it can undo, that supersedes the last MLE operation. The application can then reset its own undo state upon receipt of an MLN_ CHANGE, indicating that later changes have occurred through the MLE.

Default Processing

The default window procedure takes no action on this message, other than to set ReturnCode to 0.