使用加密的Sqlite-net-pcl无法正常工作

I am using a nuget package sqlite-net-pcl in my .Net Standard Library application, however when i try to add a password(key) to my SQLiteConnectionString, it doesn't seem to work. Because i can access the file through SQLite Manager without providing my key password. How do i fix this?

I copied and paste the example from Github repository (last section) to my application. This is the summary of my code.

public class SQLiteDatabaseConnection
    {
        public SQLiteConnectionString SqliteConnectionString { get; private set; }
        public SQLiteAsyncConnection SqliteConnection { get; private set; }

        public SQLiteDatabaseConnection(string pathDirectory = null, string name = "my_database", string key = null)
        {
            string directory = pathDirectory ?? Environment.CurrentDirectory;
            string databasePath = Path.Combine(directory, $"{name}.sqlite3");

            this.SqliteConnectionString = new SQLiteConnectionString(databasePath, true, key: key);
            this.SqliteConnection = new SQLiteAsyncConnection(this.SqliteConnectionString) ?? throw new ArgumentNullException(nameof(this.SqliteConnection));
        }
    }

And in my Repository, i created an instance of SQLiteDatabaseConnection

 string path = Environment.CurrentDirectory;
 SQLiteDatabaseConnection connection = new SQLiteDatabaseConnection(path, "database_test", "my_password");
 _repository = new RepositoryWrapper(connection);

I expect that the database_test.sqlite3 can't be access from any SQLite Manager, which i discussed above. Or the file database can be access only through my application.

该代码在创建表,插入,删除等时完美工作。 但是,我想保护文件。

对不起,我的英语不好。并预先感谢您。 如果您对解决方案还有其他建议或链接,我将不胜感激。