static void Main(string[] args) { string exePath = @"F:\C_shap\Git\MyORM\trunk\TestApp"; string mySQL_conStr = "Your MySQL connection string"; string sqlServer_conStr = @"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=" + exePath + @"\TestDataBases\SQLServerDB.mdf" + ";Integrated Security=True;Connect Timeout=30"; string sqlite_conStr = @"Data Source=" + exePath + @"\TestDataBases\SQLiteDB.db"; // step 1 SetConnectionString MySQLService.SetConnection(mySQL_conStr); SQLServerService.SetConnection(sqlServer_conStr); SQLiteService.SetConnection(sqlite_conStr); DataBaseTypesEnum DBType = DataBaseTypesEnum.SQLite; SQLService service = null; switch (DBType) { case DataBaseTypesEnum.MySQL: { //step 2 tell Service that which type of database you want to use in default ModelBase.SetDefaultService(DataBaseTypesEnum.MySQL); //step 3 create a new instance and use it service = new MySQLService(); break; } case DataBaseTypesEnum.SQLServer: { ModelBase.SetDefaultService(DataBaseTypesEnum.SQLServer); service = new SQLServerService(); break; } case DataBaseTypesEnum.SQLite: { ModelBase.SetDefaultService(DataBaseTypesEnum.SQLite); service = new SQLiteService(); break; } } LoadById(service); ReadAll(service); ReadByCondition(service); ReadPageList(service); Update(service); Insert(service); Delete(service); Console.ReadKey(); }