Solved

Clearing the keyboard buffer

Posted on 2001-06-07
6
404 Views
Last Modified: 2010-04-06
How can I clear the keyboard buffer? Is there an API?
0
Comment
Question by:alexandram
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
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;
0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 3

Accepted Solution

by:
f15iaf earned 200 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
ADMINISTRATION WILL BE CONTACTING YOU SHORTLY.  Moderators Computer101 or Netminder will return to finalize these if still open in seven days.  Please post closing recommendations before that time.

Question(s) below appears to have been abandoned. Your options are:
 
1. Accept a Comment As Answer (use the button next to the Expert's name).
2. Close the question if the information was not useful to you, but may help others. You must tell the participants why you wish to do this, and allow for Expert response.  This choice will include a refund to you, and will move this question to our PAQ (Previously Asked Question) database.  If you found information outside this question thread, please add it.
3. Ask Community Support to help split points between participating experts, or just comment here with details and we'll respond with the process.
4. Delete the question (if it has no potential value for others).
   --> Post comments for expert of your intention to delete and why
   --> You cannot delete a question with comments, special handling by a Moderator is required.

For special handling needs, please post a zero point question in the link below and include the URL (question QID/link) that it regards with details.
http://www.experts-exchange.com/jsp/qList.jsp?ta=commspt
 
Please click the Help Desk link on the left for Member Guidelines, Member Agreement and the Question/Answer process for further information, if needed.  http://www.experts-exchange.com/jsp/cmtyHelpDesk.jsp

Click you Member Profile to view your question history and keep them all current with updates as the collaboration effort continues, to track all your open and locked questions at this site.  If you are an EE Pro user, use the Power Search option to find them.  Anytime you have questions which are LOCKED with a Proposed Answer but does not serve your needs, please reject it and add comments as to why.  In addition, when you do grade the question, if the grade is less than an A, please add a comment as to why.  This helps all involved, as well as future persons who may access this item in the future to seek help.

To view your open questions, please click the following link(s) and keep them all current with updates.
http://www.experts-exchange.com/questions/Q.20132480.html
http://www.experts-exchange.com/questions/Q.20139932.html
http://www.experts-exchange.com/questions/Q.20259533.html


To view your locked questions, please click the following link(s) and evaluate the proposed answer.
http://www.experts-exchange.com/questions/Q.20131492.html

PLEASE DO NOT AWARD THE POINTS TO ME.  
 
------------>  EXPERTS:  Please leave any comments regarding your closing recommendations if this item remains inactive another seven (7) days.  Also, if you are interested in the cleanup effort, please click this link http://www.experts-exchange.com/jsp/qManageQuestion.jsp?ta=commspt&qid=20274643

Moderators will finalize this question if still open in 7 days, by either moving this to the PAQ (Previously Asked Questions) at zero points, deleting it or awarding expert(s) when recommendations are made, or an independent determination can be made.  Expert input is always appreciated to determine the fair outcome.
 
Thank you everyone.
 
Moondancer
Moderator @ Experts Exchange
0
 
LVL 1

Expert Comment

by:Moondancer
ID: 7079949
Zero response, finalized by Moondancer - EE Moderator
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

A lot of questions regard threads in Delphi.   One of the more specific questions is how to show progress of the thread.   Updating a progressbar from inside a thread is a mistake. A solution to this would be to send a synchronized message to the…
Hello everybody This Article will show you how to validate number with TEdit control, What's the TEdit control? TEdit is a standard Windows edit control on a form, it allows to user to write, read and copy/paste single line of text. Usua…
Nobody understands Phishing better than an anti-spam company. That’s why we are providing Phishing Awareness Training to our customers. According to a report by Verizon, only 3% of targeted users report malicious emails to management. With compan…
Attackers love to prey on accounts that have privileges. Reducing privileged accounts and protecting privileged accounts therefore is paramount. Users, groups, and service accounts need to be protected to help protect the entire Active Directory …

756 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question