Solved

TEdit OnKeyPress Event help

Posted on 2010-09-13
4
357 Views
Last Modified: 2012-05-10
I have a function that converts a number to roman and visa versa. (thanks to EE expert).

I need to prevent users from entering anything other than the following characters

0..9, or  I,V,X,L,C,D,M

into a TEdit control

I guess i need to allow a backspace, but nothing else. (example, no spaces, periods, etc. etc)

thanks
0
Comment
Question by:Looking_4_Answers
  • 2
4 Comments
 

Author Comment

by:Looking_4_Answers
ID: 33666498
sorry, i meant to rephrase it

if not (Key in [#8, '0'..'9', 'I','V','X','L','C','D','M']) then
  Key := #0;

i need to prevent the person from entering a numeric if they are already entering a roman numeral character, and visa versa (if the enter a 'I','V','X','L','C','D','M'  then they can't enter a 0..9
0
 
LVL 25

Accepted Solution

by:
epasquier earned 250 total points
ID: 33666932
Voila !
procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);

Var

 Txt:String;

 i64:Int64;

 SetAllowed:Set of Char;

Const

 AllowDigits=['0'..'9'];

 AllowRomans=['I','V','X','L','C','D','M'];

begin

 Txt:=(Sender As TEdit).Text;

 if Txt='' Then SetAllowed:=AllowDigits+AllowRomans Else

  if TryStrToInt64(Txt,i64)

   Then SetAllowed:=AllowDigits

   Else SetAllowed:=AllowRomans;

 SetAllowed:=SetAllowed+[#8];

 Key:=UpCase(Key); // convert i, v, x... to I, V, X

 If Not (Key In SetAllowed) Then Key:=#0;

end;

Open in new window

0
 
LVL 9

Expert Comment

by:Mahdi78
ID: 33667012
Great !
Très bonne idée.
0
 

Author Closing Comment

by:Looking_4_Answers
ID: 33674904
NICE JOB!  Thanks!
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

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…
Have you ever had your Delphi form/application just hanging while waiting for data to load? This is the article to read if you want to learn some things about adding threads for data loading in the background. First, I'll setup a general applica…
Get a first impression of how PRTG looks and learn how it works.   This video is a short introduction to PRTG, as an initial overview or as a quick start for new PRTG users.
Delivering innovative fully-managed cloud services for mission-critical applications requires expertise in multiple areas plus vision and commitment. Meet a few of the people behind the quality services of Concerto.

932 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

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now