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...restrict input in edit boxes?
Autor: Rafael Giusti
[ Print tip ]  

Tip Rating (2):  
     


{
  In this exemple, the only keys allowed are the
  same allowed in e-mail adresses.
}

procedure TForm1.Edit1KeyPress(Sender: TObject;
  var Key: Char);
const
  
AllowedChars: string = 'abcdefghijklmnopq' +
    'rstuvwxyz01234567_.@';
var
  
i: Integer;
  Ok: Boolean;
begin
  
i  := 0;
  Ok := False;
  { If you erase next line, user won't be able to type backspace }
  
if Key = #8 then Ok := True;
  repeat
    
i := i + 1;
    if Key = AllowedChars[i] then Ok := True;
  until (Ok) or (i = Length(AllowedChars));
  if not Ok then Key := #0;
end;


 

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