C＃/ SQL：通过复制和替换数据库文件进行备份和还原？

Question

首先，这是一种分享知识而非问题。

我通过使用备份和恢复命令的默认方法遇到了创建数据库备份和恢复的一些问题所以我通过处理数据库文件开发了自己的数据库并在需要时将其恢复

我会分享它，以帮助他人。

Answer 1

解决方案：

首先，您必须知道在复制或替换数据库文件之前，您必须将数据库设置为脱机状态，并在完成后将其重新联机。

1）使用的方法

 // fullPath : the path for your database
 // executablePath : the path for your exe folder

    void setFullPath()
    {
        string executable = System.Reflection.Assembly.GetExecutingAssembly().Location;
        executablePath = (System.IO.Path.GetDirectoryName(executable));
        fullPath = executablePath + "\\Database.mdf";
    }

    void takeOffline(string fullPath)
    {
        homeObject.connection.Open();
        homeObject.cmd.CommandText = "ALTER DATABASE [" + fullPath + "] SET OFFLINE";
        homeObject.cmd.ExecuteNonQuery();
        homeObject.cmd.Clone();
    }

    void bringOnline(string fullPath)
    {
        homeObject.cmd.CommandText = "ALTER DATABASE [" + fullPath + "] SET ONLINE"; ;
        homeObject.cmd.ExecuteNonQuery();
        homeObject.cmd.Clone();
        homeObject.connection.Close();
    }

2）复制数据库文件/备份

  bool getDatabaseCopy()
    {
        try
        {
            //
            takeOffline(fullPath);

            // copy database.mdf
            copyDBMDF();

            // copy database_log.ldf
            copyDB_logLDF();

            //
            bringOnline(fullPath);

            return true;
        }
        catch
        {
            //
        }

        return false;
    }

    // txtPath.txt :
    // folder location to save database files in

    void copyDBMDF()
    {
        string fileName = "Database.mdf";

        string sourceFile = fullPath;
        string targetPath = txtPath.Text;

        // Use Path class to manipulate file and directory paths.
        string destFile = System.IO.Path.Combine(targetPath, fileName);

        // To copy a folder's contents to a new location:
        // Create a new target folder, if necessary.
        if (!System.IO.Directory.Exists(targetPath))
        {
            System.IO.Directory.CreateDirectory(targetPath);
        }

        // To copy a file to another location and 
        // overwrite the destination file if it already exists.
        System.IO.File.Copy(sourceFile, destFile, true);
    }

    void copyDB_logLDF()
    {
        string fileName = "Database_log.ldf";

        string sourcePath = executablePath;
        string targetPath = txtPath.Text;

        // Use Path class to manipulate file and directory paths.
        string sourceFile = System.IO.Path.Combine(sourcePath, fileName);
        string destFile = System.IO.Path.Combine(targetPath, fileName);

        // To copy a folder's contents to a new location:
        // Create a new target folder, if necessary.
        if (!System.IO.Directory.Exists(targetPath))
        {
            System.IO.Directory.CreateDirectory(targetPath);
        }

        // To copy a file to another location and 
        // overwrite the destination file if it already exists.
        System.IO.File.Copy(sourceFile, destFile, true);
    }

3）用您复制/恢复的文件替换当前数据库文件

  bool restoreTheBackup()
    {
        try
        {
            //
            takeOffline(fullPath);

            // load .mdf
            loadMDFDatabaseFile();

            // load _log.ldf
            loadLDFDatabaseFile();

            //
            bringOnline(fullPath);

            return true;
        }
        catch
        {
            //
        }

        return false;
    }

// txtPath.txt :
// location to get database files from to replace with current files.

    void loadLDFDatabaseFile()
    {
        string fileName = "Database_log.ldf";

        string targetPath = executablePath;
        string sourcePath = txtPath.Text;

        // Use Path class to manipulate file and directory paths.
        string sourceFile = System.IO.Path.Combine(sourcePath, fileName);
        string destFile = System.IO.Path.Combine(targetPath, fileName);

        // To copy a folder's contents to a new location:
        // Create a new target folder, if necessary.
        if (!System.IO.Directory.Exists(targetPath))
        {
            System.IO.Directory.CreateDirectory(targetPath);
        }

        // To copy a file to another location and 
        // overwrite the destination file if it already exists.
        System.IO.File.Copy(sourceFile, destFile, true);
    }

    void loadMDFDatabaseFile()
    {
        string fileName = "Database.mdf";

        string targetPath = executablePath;
        string sourcePath = txtPath.Text;

        // Use Path class to manipulate file and directory paths.
        string sourceFile = System.IO.Path.Combine(sourcePath, fileName);
        string destFile = System.IO.Path.Combine(targetPath, fileName);

        // To copy a folder's contents to a new location:
        // Create a new target folder, if necessary.
        if (!System.IO.Directory.Exists(targetPath))
        {
            System.IO.Directory.CreateDirectory(targetPath);
        }

        // To copy a file to another location and 
        // overwrite the destination file if it already exists.
        System.IO.File.Copy(sourceFile, destFile, true);
    }