private void btn_showStatistic_Click(object sender, EventArgs e)
        {
            UnityController uc = new UnityController();
            SaveFileDialog  saveFileDialog1 = new SaveFileDialog();

            saveFileDialog1.FileName = "temp.txt";
            uc.ShowSalesStatistics(saveFileDialog1.FileName, dateTimePicker_from.Value, dateTimePicker_to.Value);
            string content = File.ReadAllText(saveFileDialog1.FileName);

            richTextBox1.Text = content;
        }
        private void btn_printStatistic_Click(object sender, EventArgs e)
        {
            UnityController uc = new UnityController();
            SaveFileDialog  saveFileDialog1 = new SaveFileDialog();

            saveFileDialog1.InitialDirectory = @"C:\";
            saveFileDialog1.FileName         = ".txt";
            saveFileDialog1.CheckFileExists  = false;
            saveFileDialog1.CheckPathExists  = true;
            saveFileDialog1.DefaultExt       = "txt";
            saveFileDialog1.Filter           = "Text files (*.txt)|*.txt|All files (*.*)|*.*";
            saveFileDialog1.FilterIndex      = 2;
            saveFileDialog1.RestoreDirectory = true;
            if (saveFileDialog1.ShowDialog() == DialogResult.OK)
            {
                uc.ShowSalesStatistics(saveFileDialog1.FileName, dateTimePicker_from.Value, dateTimePicker_to.Value);
                MessageBox.Show("Din fil er nu gemt på den valgte destination");
            }
            else
            {
                MessageBox.Show("Din fil blev ikke gemt. Du skal oprette en textfil og vælge den i promptvinduet.");
            }
        }