将自定义SO文件导入AOSP(importing custom SO file to AOSP)

 MS Access数据库的备份是文件副本。 
 
 从baseDirectory开始，使用Path.Combine，您可以构建包含baseDirectory和day的fullDirectory名称。 之后，您可以将文件（File.Copy）复制到该目录（最终使用Path.Combine构建文件的fullPath）。 不要忘记在复制文件之前处理连接，并确保在复制时没有人使用该文件。 
 
 编辑 
 
using System;
using System.IO;

public class Program
{
    public static void Main()
    {

        string baseDirectory = "C:\\Insert\\Your\\Base\\Directory";
        string mdbSourceFilePath = "C:\\Directory\\Of\\mdb\\MyAccessDb.accdb";
        string mdbTargetFileName = "MyAccessDb.bk";

        string fullDirectory = Path.Combine(baseDirectory, DateTime.Today.ToString("dddd"));
        if (!Directory.Exists(baseDirectory))
            Directory.CreateDirectory(baseDirectory);
        if (!Directory.Exists(fullDirectory))
            Directory.CreateDirectory(fullDirectory);

        string mdbTargetFilePath = Path.Combine(fullDirectory, mdbTargetFileName);

        File.Copy(mdbSourceFilePath, mdbTargetFilePath);


    }


}

Backup of MS Access database is a file copy.
 
Starting from a baseDirectory, with Path.Combine you can build a fullDirectory name containing the baseDirectory and the day. After that you can copy the file (File.Copy) to that directory (eventually using Path.Combine to build a fullPath of the file). Don't forget to Dispose the connection before copying the file and be sure the no one is using the file when you make the copy.
 
EDIT
 
using System;
using System.IO;

public class Program
{
    public static void Main()
    {

        string baseDirectory = "C:\\Insert\\Your\\Base\\Directory";
        string mdbSourceFilePath = "C:\\Directory\\Of\\mdb\\MyAccessDb.accdb";
        string mdbTargetFileName = "MyAccessDb.bk";

        string fullDirectory = Path.Combine(baseDirectory, DateTime.Today.ToString("dddd"));
        if (!Directory.Exists(baseDirectory))
            Directory.CreateDirectory(baseDirectory);
        if (!Directory.Exists(fullDirectory))
            Directory.CreateDirectory(fullDirectory);

        string mdbTargetFilePath = Path.Combine(fullDirectory, mdbTargetFileName);

        File.Copy(mdbSourceFilePath, mdbTargetFilePath);


    }


}