ibegin:= richedit1.FindText(Edit1.Text,ibegin,Length(RichEdit1.text),[stMatchCase]);
  if ibegin <> -1 then
  begin
    RichEdit1.SetFocus;
    RichEdit1.SelStart:=ibegin;
    RichEdit1.SelLength:=1;
    inc(ibegin);
  end
  else if ibegin = -1 then
  begin
    ibegin:= 0;
    Application.MessageBox('没找到变量','提示',MB_OKCANCEL+mb_iconinformation);

  end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OPenDialog1.Execute then
  begin
    RichEdit1.Lines.LoadFromFile(OpenDialog1.FileName);
  end;
end;

procedure TForm1.BitBtn1Click(Sender: TObject);
begin
  with RichEdit1 do
  begin
    SelStart:= Length(text);
    Perform(EM_SCROLL,0,0);
  end;
end;

procedure TForm1.BitBtn2Click(Sender: TObject);
begin
  with RichEdit1 do
  begin
    Perform(EM_SCROLL,SB_LINEDOWN,0);
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
  begin
    RichEdit1.Lines.LoadFromFile(OpenDialog1.FileName);
  end;
end;

end.