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Clearing the keyboard buffer

Posted on 2001-06-07
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Last Modified: 2010-04-06
How can I clear the keyboard buffer? Is there an API?
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Question by:alexandram
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6 Comments
 
LVL 5

Expert Comment

by:alanwhincup
ID: 6164869
You could use this function to remove all pending key messages from your own apps message queue.

procedure EmptyKeyQueue;
var
  Msg : TMsg;
begin
  while PeekMessage(Msg, 0, WM_KEYFIRST, WM_KEYLAST, PM_REMOVE or PM_NOYIELD) do;
end;

Cheers,

Alan
0
 
LVL 5

Expert Comment

by:alanwhincup
ID: 6164876
Also you may want to try this:

MemW[$0000 : $041C] := MemW[$0000 : $041A];
0
 
LVL 13

Expert Comment

by:Epsylon
ID: 6164880
I'm not sure if this will fit in you app:


procedure TForm1.FlushKeyboard;
var kp: Boolean;
begin
  kp := KeyPreview;
  KeyPreview := true;
  OnKeyPress := FormKeyPress;
  Application.ProcessMessages;
  OnKeyPress := nil;
  KeyPreview := kp;
end;

procedure TForm1.FormKeyPress(Sender: TObject; var Key: Char);
begin
  key := Chr(0);
end;
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LVL 3

Accepted Solution

by:
f15iaf earned 800 total points
ID: 6168043
here is the answer:
var
        k:Tkeyboardstate;
        i:integer;
begin
        for i:=0 to 255 do
        begin
                k[i]:=0;
        end;
        setkeyboardstate(k);
end;

Pay attention that capslock,scrool lock and num lock lights turns off.
0
 
LVL 1

Expert Comment

by:Moondancer
ID: 6911779
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LVL 1

Expert Comment

by:Moondancer
ID: 7079949
Zero response, finalized by Moondancer - EE Moderator
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