直接上代码：

    class DBHelperSqlite

    {

        ILog logger = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

        private string dbName = "cmcc2.db";

        private string connectionString = "Data Source=cmcc2.db;Pooling=true;FailIfMissing=false";

        /// <summary>

        /// if the db is not exists,create it and create the table

        /// </summary>

        public DBHelperSqlite()

        {

            string SQLCreateStr = "CREATE TABLE [cmcc_businesses_info] (businessName nvarchar(50),businessDate nvarchar(10),indb_datetime nvarchar(20))";

            #region CASE2

            FileInfo fi = new FileInfo(dbName);

            if (fi.Exists == false)

            {

                logger.InfoFormat("db不存在");

                //Console.WriteLine("db不存在");

                SQLiteConnection.CreateFile(dbName);

                logger.InfoFormat("db创建完成");

                using (SQLiteConnection conn = new SQLiteConnection(connectionString))

                {

                    conn.Open();

                    using (SQLiteCommand cmd = new SQLiteCommand(SQLCreateStr, conn))

                    {

                        if (cmd.ExecuteNonQuery() > 0)

                        {

                            logger.InfoFormat("表创建成功");

                            //Console.WriteLine("表创建成功");

                        }

                    }

                }

            }

            #endregion

        }//ctor

        /// <summary>

        /// 执行多条SQL语句，实现数据库事务。

        /// </summary>

        /// <param name="SQLStringList">多条SQL语句</param>

        public void ExecuteSqlTran(IList<string> SQLStringList)

        {

            using (SQLiteConnection conn = new SQLiteConnection(connectionString))

            {

                conn.Open();

                SQLiteCommand cmd = new SQLiteCommand();

                cmd.Connection = conn;

                SQLiteTransaction tran = conn.BeginTransaction();

                cmd.Transaction = tran;

                try

                {

                    for (int n = 0; n < SQLStringList.Count; n++)

                    {

                        string strsql = SQLStringList[n].ToString();

                        if (strsql.Trim().Length > 1)

                        {

                            cmd.CommandText = strsql;

                            cmd.ExecuteNonQuery();

                        }

                    }

                    tran.Commit();

                }

                catch (System.Data.SQLite.SQLiteException ex)

                {

                    logger.Error(ex);

                    tran.Rollback();

                    throw new Exception(ex.Message);

                }

            }

        }//trans

        /// <summary>

        /// execute sql.get the return

        /// </summary>

        /// <returns></returns>

        public IDictionary<string, string> ExecuteReader()

        {

            IDictionary<string, string> dic = new Dictionary<string, string>();

            using (SQLiteConnection conn = new SQLiteConnection(connectionString))

            {

                conn.Open();

                string SQLStr = "select businessname,max(businessDate) from cmcc_businesses_info group by businessname";

                using (SQLiteCommand cmd = new SQLiteCommand(SQLStr, conn))

                {

                    SQLiteDataReader reader = cmd.ExecuteReader();

                    while (reader.Read())

                    {

                        string key = reader.GetString(0);

                        string value = reader.GetString(1);

                        if (dic.ContainsKey(key))

                        {

                            Console.WriteLine("已存在：" + key + "\t" + value);

                        }

                        else

                        {

                            dic.Add(key, value);

                        }

                    }

                }

            }

            return dic;

        }

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