unit Unit1;

interface

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

const
   UM_RESETFORM = WM_USER+100;

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Edit2: TEdit;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private-Deklarationen }
    procedure HandleResetForm(var Message: TMessage); message UM_RESETFORM;
  public
    { Public-Deklarationen }
  end;

var
  Form1: TForm1;

implementation

uses Consts;

{$R *.DFM}

procedure ResetForm(const frm:TForm);
begin
   if Assigned(frm) then
   begin
      // Alle Komponenten auf dem Formular löschen
      while frm.ComponentCount > 0 do
         frm.Components[0].Free;
      (*
      frm.Name := '';
      Screen.RemoveForm(frm);  // leider kann diese Methode nicht aufgerufen werden :-(
      frm.Create(frm.Owner);  // sonst könnte man den Konstruktor aufrufen
      *)
      // Komponenten neu laden
      if not InitInheritedComponent(frm, TForm) then
         raise EResNotFound.CreateFmt(SResNotFound, [frm.ClassName]);
      frm.Visible := True;
   end;
end;


procedure TForm1.Button1Click(Sender: TObject);
begin
   // Message an das eigene Formular schicken
   PostMessage(Self.Handle, UM_RESETFORM, 0, 0);
end;

procedure TForm1.HandleResetForm(var Message: TMessage);
begin
   ResetForm(Self);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
   Edit1.Text := 'Hallo';
   Edit2.Text := 'TESTTEST';
end;

end.