asked on

Controlling edit box entering

I have tried using TMaskEdit to mask input from edit boxes, but it is too restrictive. What I need to do is know where abouts the cursor is in the box, i.e. where abouts the character being entered is going to go. e.g. I want user to enter a string MONH21 where if the first letter is m then mon appears, if it is t tue appears, I also only want the letters H or B to be entered in the 4th position and the TEditMask deals with the two digits on the end.
I have another similar situation, where I want floats to be entered to 4dp with 3places to the left of the dp. So - when 3 digits have been entered and there isn't a dp there yet, one appears in the right place, also if someone presses '.' then I want the dp to move to where the user is positioned. I thought that the position of the cursor could be determined by the StartSel property of edit boxes and the SelLength would be zero if there was only a cursor flashing.
Does anyone know how to find the cursor pos?
Thanks in advance -
jimshort@ndirect.co.uk

ZifNab

SelLength end StartLen are used when you select a text in the editbox.

Use Onkeypress event.
In event use method GetTextLen, it gives you the length of the total entered characters in the editbox. -> So if user just types in you can use this method to find the position of the cursor.

If user uses insert. Maybe you can make then a smart finder of the entered character. You've got the entered character (Key), you've got the whole text (Text). And you've got a function for finding a key in a string (Pos).

Need help, just ask;
ZifNab;

jimshort

ASKER

Sorry, I'm afraid I knew that. The bit I want to know about is the bit you didn't answer. I can do a pos(text, 'c') in the onchange event after they have put the letter in, but what if I want to use numbers like in the second example - how do I tell which is the last zero put in in a string of zeros? I am sure in some language the seltext gives you the cursor pos, but it doesn't in Delphi1. It seems as though I will have to validate the text in the edit box after every alteration is made, but the combinations of these are huge - how many different states can the edit box be in - hundreds.
So are you saying that there is no way of finding the cursor position in an edit box in Delphi?
Cheers for the answer though.

ZifNab

I don't know a direct way. Sorry
This can sound silly but maybe it's a solution.

1.Use the OnKeyPress event.
2.Use a variable of type string. OLDWORD
3.Look for the key into text of the editbox.
4.Look the change in text of editbox and OLDWORD
5. --> GIVES you the right position of the new key
6.Put the text of the editbox into the var OLDWORD

Have fun,
ZifNab;

ZifNab

Maybe there is a solution:

Try this 2 Edit box sample below.

unit Cursor;

interface

uses
SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,
Forms, Dialogs, StdCtrls;

type
TForm1 = class(TForm)
Edit1: TEdit;
Edit2: TEdit;
procedure Edit1Change(Sender: TObject);
procedure Edit1KeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
private
{ Private declarations }
public
{ Public declarations }
CurPos : integer;
end;

var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Edit1Change(Sender: TObject);
begin
CurPos := Edit1.SelStart;
edit2.Text := IntToStr(CurPos);
end;

procedure TForm1.Edit1KeyDown(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
If Key = VK_LEFT then dec(CurPos);
if Key = VK_RIGHT then inc(CurPos); {RIGHT Arrow}
edit2.text := inttostr(CurPos);
end;

Have fun,
c.u. ZifNab;

ASKER CERTIFIED SOLUTION

millerw

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