private void Button_Filter_Click(object sender, RoutedEventArgs e)
        {
            string line;


            TextBox_LOG.Text = "";


            using (StreamReader r = File.OpenText("log.txt"))
            {
                while ((line = r.ReadLine()) != null)
                {
                    String   substring = line.Substring(9, 15);
                    DateTime dt        = Convert.ToDateTime(substring);
                    DateTime dtod      = Convert.ToDateTime(DatumOd.Text);
                    DateTime dtdo      = Convert.ToDateTime(DatumDo.Text);

                    if (dt >= dtod && dt <= dtdo)
                    {
                        TextBox_LOG.Text = TextBox_LOG.Text + line + "\n";
                    }
                }
            }

            TextBox_LOG.Select(TextBox_LOG.Text.Length, 0);
        }
        // Ucitaj Log
        public void UcitajLog()
        {
            string line;

            TextBox_LOG.Text = "";

            using (StreamReader r = File.OpenText("log.txt"))
            {
                while ((line = r.ReadLine()) != null)
                {
                    TextBox_LOG.Text = line + "\n" + TextBox_LOG.Text;
                }
            }

            TextBox_LOG.Select(TextBox_LOG.Text.Length, 0);
        }