With this method you can read a TEdit from another application. For instance the TEdit containing the internet address from MS-IE.

(* You'll need a form with a TEdit, a Timer and a Label on it.
1) Open two instances of this application.
2) Enter a text in the TEdit of application 1.
3) Just look at what you see in the label of application 2 if you go with the mouse over the TEdit of application 1
Do you get the point? *)

// Modified 28/02/2002
// Added WM_GETTEXT
// By WM_GETTEXT f.i. the passwordbox of Excel can be read
// Now the application also reads EditBox (not only TEdit, Edit and RichEdit)
// Added ChildWindowFromPoint (thanks to Scalabium)

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ExtCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Timer1: TTimer;
    Procedure FormCreate(Sender : TObject);
    Procedure FormClose(Sender: TObject; var Action: TCloseAction);
    Procedure Timer1Timer(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;
  Bo     : Boolean;

implementation

{$R *.DFM}

procedure TForm1.FormCreate(Sender: TObject);
begin
Edit1.PasswordChar := '*';
Bo := False;
Timer1.Interval := 250;
Timer1.Enabled := True;
Edit1.Text := '';
Label1.Caption := '';
end;

procedure TForm1.Timer1Timer(Sender: TObject);

Var
   p             : TPoint;
   x,y,oldx,oldy : Integer;
   s             : String;
   b             : Array[0..255] of Char;
   i,j,l         : Integer;
   h,oldh, h1    : Thandle;

begin
Timer1.Enabled := False;
oldx := 0;
oldy := 0;
oldh := 0;
Repeat
   Application.ProcessMessages;
   GetCursorPos(p);
   x := p.x;
   y := p.y;
   h := WindowFromPoint(p);
   h1 := ChildWindowFromPoint(h,p);
   If h1 <> 0 then
      h := h1;

   if (oldx <> x) or (oldy <> y) then
      if h <> oldh then
         Begin
         FillChar(b,255,#0);
         b[0] := #255;
         j := integer(@b);
         i := SendMessage(h,EM_GETPASSWORDCHAR,0,0); // no encryption
         l := SendMessage(h,EM_GETLINE,0,j); // get line
         If l = 0 then
            SendMessage(h,WM_GETTEXT,sizeof(b),j);
         SendMessage(h,EM_SETPASSWORDCHAR,i,0); // encrypt back
         s := StrPas(b);
         If s <> '' then
            Label1.Caption := s; // show unencrypted line
         oldh := h;
         oldx := x;
         oldy := y;
         End;

Until Bo;
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
Bo := True;
end;

end.