how do i ..?

how do i get the last action perform by a user
and then undo it?
like the notepad application, u type in some words
and u undo..that is delete ..and then undo...u get the words
back..and change font back etc..
superboyAsked:
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WaldekCommented:
I think You must save some parametersin list of history. If user select undo You must go to history and back with saved information
0
julio011597Commented:
To give you some code would be very involving (even if the points were 200).

Would you be satisfied with a "the way to go"?
0
dvalineCommented:
If you search the registry you'll notice that alot of the undo information is written and extracted form the registry.  You need to come up with a schema to be able to get in out values that you can interpret to actions.
0
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superboyAuthor Commented:
is there another way besides using the registry?
0
d003303Commented:
- create an action object that encapsulates ANY operation that can be done in your program
- keep a history list that stores action objects
- After each action, create a new action object with the new document state and set the old action object to the history list

Slash/d003303
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jpussacqCommented:
Supose that you are using a TRichEdit.
To get the last action perform by a user in the RichEdit1,
write the following lines in the Button "Undo" OnClick event:

if RichEdit1.HandleAllocated then
   SendMessage(RichEdit1.Handle, EM_UNDO, 0, 0);



0
jpussacqCommented:
Supose that you are using a TRichEdit.
To get the last action perform by a user in the RichEdit1,
write the following lines in the Button "Undo" OnClick event:

  if RichEdit1.HandleAllocated then
     SendMessage(RichEdit1.Handle, EM_UNDO, 0, 0);


0

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