using System.IO;

        private void BtnDataBackup_Click(object sender, EventArgs e)
        {//数据备份按钮
            string dbFilePath = Application.StartupPath + @"\data\orders.db";
            string dbNewFilePath=Application.StartupPath + @"\data\backup\orders"+ DateTime.Now.ToString("yyyyMMddHHmmss") + ".db";
            string dirPath=Application.StartupPath + @"\data\backup";
            try
            {
                if (!Directory.Exists(dirPath))
                {//创建backup文件夹
                    Directory.CreateDirectory(dirPath);
                }
                File.Copy(dbFilePath, dbNewFilePath);//拷贝文件
                if (File.Exists(dbNewFilePath))
                {
                    labMsg.Text="数据库文件备份成功,文件路径： " + dbNewFilePath;
                }
            }
            catch
            {
                labMsg.Text="数据备份失败,备份的同时，不要进行其他操作!";
            }
        }

        private void BtnDataRecovery_Click(object sender, EventArgs e)
        {//数据恢复按钮
            string backUpDir = Application.StartupPath + @"\data\backup";
            string dbFilePath = Application.StartupPath + @"\data\orders.db";
            //选择文件
            openFileDialog1.Filter = "db文件|*.db";//筛选文件类型
            openFileDialog1.InitialDirectory = backUpDir;
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {//恢复[覆盖]文件
                File.Copy(openFileDialog1.FileName, dbFilePath, true);//拷贝文件，存在则覆盖（也可以弹messagebox，让用户选择是否覆盖）
                if (File.GetLastWriteTime(openFileDialog1.FileName).ToString("yyyyMMddHHmmss") == File.GetLastWriteTime(dbFilePath).ToString("yyyyMMddHHmmss"))
                {//通过比较2个文件的修改日期，进行判断
                    labMsg.Text = "数据恢复成功。";
                }
                else
                {
                    labMsg.Text = "数据恢复失败，请手动拷贝文件进行恢复。";
                }
            }
            openFileDialog1.Dispose();
        }