參考資料來源：
    https://www.youtube.com/watch?v=-fl7PQ7vpCY&ab_channel=CsharpTutorials
    https://csharp-tutorials1.blogspot.com/2016/03/backup-and-restore-sql-server-database.html

    函式庫：
    using System;
    using System.Windows;
    using System.Windows.Forms;
    using System.Data.SqlClient;
    using System.Data;

    聲明數據庫的connectionString：

    1. SqlConnection con = new SqlConnection(Final_window.Properties.Settings.Default.Final_windowConnectionString);

    備份：
    選擇備份路徑（備份到哪一個文件夾中）

    1. private void browseButton_Click(object sender, EventArgs e)
    2. {
    3.     FolderBrowserDialog dlg = new FolderBrowserDialog();
    4.     if (dlg.ShowDialog() == DialogResult.OK)
    5.     {
    6.          textBox1.Text = dlg.SelectedPath;
    7.          BackupButton.Enabled = true;
    8.     }
    9. }

    備份並輸出

    1. private void BackupButton_Click(object sender, EventArgs e)
    2. {
    3.     string database = con.Database.ToString();
    4.     try
    5.     {
    6.         if(textBox1.Text==string.Empty)
    7.         {
    8.             MessageBox.Show("please enter backup file location");
    9.         }
    10.         else
    11.         {
    12.             string cmd = "BACKUP DATABASE [" + database + "] TO DISK='" + textBox1.Text + "\\" + "database" + "-" + DateTime.Now.ToString("yyyy-MM-dd--HH-mm-ss") + ".bak'";
    14.             using(SqlCommand command = new SqlCommand(cmd,con))
    15.             {
    16.                 if(con.State!=ConnectionState.Open)
    17.                 {
    18.                     con.Open();
    19.                 }
    20.                 command.ExecuteNonQuery();
    21.                 con.Close();
    22.                 MessageBox.Show("database backup done successefully");
    23.                 BackupButton.Enabled = false;
    24.             }
    25.        }
    27.     }
    28.     catch
    29.     {
    31.     }
    32. }

    復原：
    選擇路徑，選擇所要恢復的資料庫bak檔案

    1. private void Browsebutton2_Click(object sender, EventArgs e)
    2. {
    3.     OpenFileDialog dlg = new OpenFileDialog();
    4.     dlg.Filter = "SQL SERVER database backup files|*.bak";
    5.     dlg.Title = "Database restore";
    6.     if (dlg.ShowDialog() == DialogResult.OK)
    7.     {
    8.         textBox2.Text = dlg.FileName;
    9.         restoreButton.Enabled = true;
    10.     }
    11. }

    復原資料庫

    1. private void restoreButton_Click(object sender, EventArgs e)
    2. {
    3.     string database = con.Database.ToString();
    4.     if (con.State != ConnectionState.Open)
    5.     {
    6.         con.Open();
    7.     }
    8.     try
    9.     {
    10.         string sqlStmt2 = string.Format("ALTER DATABASE [" + database + "] SET SINGLE_USER WITH ROLLBACK IMMEDIATE");
    11.         SqlCommand bu2 = new SqlCommand(sqlStmt2, con);
    12.         bu2.ExecuteNonQuery();
    14.         string sqlStmt3 = "USE MASTER RESTORE DATABASE [" + database + "] FROM DISK='" + textBox2.Text + "'WITH REPLACE;";
    15.         SqlCommand bu3 = new SqlCommand(sqlStmt3, con);
    16.         bu3.ExecuteNonQuery();
    18.         string sqlStmt4 = string.Format("ALTER DATABASE [" + database + "] SET MULTI_USER");
    19.         SqlCommand bu4 = new SqlCommand(sqlStmt4, con);
    20.         bu4.ExecuteNonQuery();
    22.         MessageBox.Show("database restoration done successefully");
    23.         con.Close();
    25.    }
    26.    catch (Exception ex)
    27.    {
    28.         MessageBox.Show(ex.ToString());
    29.    }
    30. }