public void Test_GetLastAccessTimeUtc()
        {
            var storage = new DiskIsolateStorage("Test", baseDirectory);
            storage.InitStore();
            string storePath = Path.Combine(baseDirectory, "Test");

            //创建目录
            string dir = "Test" + Guid.NewGuid().ToString();
            storage.CreateDirectory(dir);
            var dirLastAccessTime = Directory.GetLastAccessTimeUtc(Path.Combine(storePath, dir));

            //创建文件
            string testString = "This is teststring";
            MemoryStream stream = new MemoryStream();
            byte[] buffer = Encoding.Default.GetBytes(testString);
            stream.Write(buffer, 0, 18);
            var filePath = Guid.NewGuid().ToString() + ".txt";
            storage.CreateFile(filePath, stream);
            FileStream fs = File.Open(Path.Combine(storePath, filePath), FileMode.Open);
            fs.Close();

            var fileLastAccessTime = File.GetLastAccessTimeUtc(Path.Combine(storePath, filePath));

            var dirResult = storage.GetLastAccessTimeUtc(dir);
            var fileResult = storage.GetLastAccessTimeUtc(filePath);

            Assert.AreEqual(dirLastAccessTime, dirResult);
            Assert.AreEqual(fileLastAccessTime, fileResult);
        }