procedure TForm1.Button1Click(Sender: TObject);
var
FoundWindow: HWND;
WindowText: array[0..255] of char;
begin
{find a TEdit child window}
FoundWindow:=FindWindowEx(Form1.Handle, 0, 'TEdit',nil);
{get its text...}
GetWindowText(FoundWindow, WindowText, 255);
{...and display it}
Label1.Caption:='FindWindowEx found window handle '+IntToStr(FoundWindow)+
': '+WindowText;
for i := 1 to Form.ComponentCount do begin
if (Form.Components[i] is TEdit) begin
case (Form.Component[i] as TEdit).tag of
1: Edit1
2: Edit2
3: Edit3
end;
end;
end;