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 CASE2FileInfo 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;}