private void btnOk_Click(object sender, EventArgs e)
        {
            try
            {
                #region Checking input
                if (!String.IsNullOrEmpty(txtNew.Text.Trim()))
                {
                    int temp = -1;
                    if (!int.TryParse(txtNew.Text.Trim(), out temp))
                    {
                        MessageBox.Show("Please enter the correct value!");
                        return;
                    }
                }
                if (txtNew.Text.Trim() == txtOld.Text)
                {
                    MessageBox.Show("The new refresh cycle is same as old refresh cycle!");
                    return;
                }
                #endregion
                string path     = Application.StartupPath + "\\SysConfig";
                string newCycle = string.Empty;
                if (string.IsNullOrEmpty(txtNew.Text.Trim()))
                {
                    newCycle = txtOld.Text.Trim() + "," + Convert.ToString(checkBox1.Checked);
                }
                else
                {
                    newCycle = txtNew.Text.Trim() + "," + Convert.ToString(checkBox1.Checked);
                }
                FileOperate.CoverOldFile(path, "RefreshCycle.txt", newCycle);
                MessageBox.Show("Success!");

                int result = 10000;
                int.TryParse(newCycle.Split(',')[0], out result);
                changeSelectedPageTimer.Interval = result;
                if (checkBox1.Checked)
                {
                    changeSelectedPageTimer.Start();
                }
                else
                {
                    changeSelectedPageTimer.Stop();
                }
                this.DialogResult = DialogResult.OK;
            }
            catch (Exception ex)
            {
                logger.Error(ex.Message);
            }
        }