C# SQLite数据库 访问封装类

时间:2022-12-11 08:16:27

在客户端配置文件<configuration>节点下,添加:

<connectionStrings>
<add name="localdb" connectionString="Data Source=config/local.db;Version=3;UseUTF16Encoding=True;" providerName="System.Data.SQLite.SQLiteFactory"/>
</connectionStrings>
其中【localdb】是本地SQLite数据库的名称,【config/local.db】是在当前程序运行目录下SQLite数据库位置

C# SQLite数据库  访问封装类代码:

 /// <summary>    /// 本类为SQLite数据库帮助静态类,使用时只需直接调用即可,无需实例化    /// </summary>    public static class SQLiteHelper    {        // Application.StartupPath        public static string LocalDbConnectionString = ConfigurationManager.ConnectionStrings["localdb"].ConnectionString;        #region ExecuteNonQuery        /// <summary>        /// 执行数据库操作(新增、更新或删除)        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="cmd">SqlCommand对象</param>        /// <returns>所受影响的行数</returns>        public static int ExecuteNonQuery(string connectionString, SQLiteCommand cmd)        {            int result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, cmd.CommandType, cmd.CommandText);                try                {                    result = cmd.ExecuteNonQuery();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        /// <summary>        /// 执行数据库操作(新增、更新或删除)        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <returns>所受影响的行数</returns>        public static int ExecuteNonQuery(string connectionString, string commandText, CommandType commandType)        {            int result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteCommand cmd = new SQLiteCommand();            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, commandType, commandText);                try                {                    result = cmd.ExecuteNonQuery();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        /// <summary>        /// 执行数据库操作(新增、更新或删除)        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <param name="cmdParms">SQL参数对象</param>        /// <returns>所受影响的行数</returns>        public static int ExecuteNonQuery(string connectionString, string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)        {            int result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteCommand cmd = new SQLiteCommand();            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, commandType, commandText);                try                {                    result = cmd.ExecuteNonQuery();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        #endregion        #region ExecuteScalar        /// <summary>        /// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="cmd">SqlCommand对象</param>        /// <returns>查询所得的第1行第1列数据</returns>        public static object ExecuteScalar(string connectionString, SQLiteCommand cmd)        {            object result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, cmd.CommandType, cmd.CommandText);                try                {                    result = cmd.ExecuteScalar();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        /// <summary>        /// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <returns>查询所得的第1行第1列数据</returns>        public static object ExecuteScalar(string connectionString, string commandText, CommandType commandType)        {            object result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteCommand cmd = new SQLiteCommand();            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, commandType, commandText);                try                {                    result = cmd.ExecuteScalar();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        /// <summary>        /// 执行数据库操作(新增、更新或删除)同时返回执行后查询所得的第1行第1列数据        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <param name="cmdParms">SQL参数对象</param>        /// <returns>查询所得的第1行第1列数据</returns>        public static object ExecuteScalar(string connectionString, string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)        {            object result = 0;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteCommand cmd = new SQLiteCommand();            using (SQLiteConnection con = new SQLiteConnection(connectionString))            {                SQLiteTransaction trans = null;                PrepareCommand(cmd, con, ref trans, true, commandType, commandText);                try                {                    result = cmd.ExecuteScalar();                    trans.Commit();                }                catch (Exception ex)                {                    trans.Rollback();                    throw ex;                }            }            return result;        }        #endregion        #region ExecuteReader        /// <summary>        /// 执行数据库查询,返回SqlDataReader对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="cmd">SqlCommand对象</param>        /// <returns>SqlDataReader对象</returns>        public static DbDataReader ExecuteReader(string connectionString, SQLiteCommand cmd)        {            DbDataReader reader = null;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, cmd.CommandType, cmd.CommandText);            try            {                reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);            }            catch (Exception ex)            {                throw ex;            }            return reader;        }        /// <summary>        /// 执行数据库查询,返回SqlDataReader对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <returns>SqlDataReader对象</returns>        public static DbDataReader ExecuteReader(string connectionString, string commandText, CommandType commandType)        {            DbDataReader reader = null;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand();            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, commandType, commandText);            try            {                reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);            }            catch (Exception ex)            {                throw ex;            }            return reader;        }        /// <summary>        /// 执行数据库查询,返回SqlDataReader对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <param name="cmdParms">SQL参数对象</param>        /// <returns>SqlDataReader对象</returns>        public static DbDataReader ExecuteReader(string connectionString, string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)        {            DbDataReader reader = null;            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand();            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, commandType, commandText, cmdParms);            try            {                reader = cmd.ExecuteReader(CommandBehavior.CloseConnection);            }            catch (Exception ex)            {                throw ex;            }            return reader;        }        #endregion        #region ExecuteDataSet        /// <summary>        /// 执行数据库查询,返回DataSet对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="cmd">SqlCommand对象</param>        /// <returns>DataSet对象</returns>        public static DataSet ExecuteDataSet(string connectionString, SQLiteCommand cmd)        {            DataSet ds = new DataSet();            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, cmd.CommandType, cmd.CommandText);            try            {                SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);                sda.Fill(ds);            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (cmd.Connection != null)                {                    if (cmd.Connection.State == ConnectionState.Open)                    {                        cmd.Connection.Close();                    }                }            }            return ds;        }        /// <summary>        /// 执行数据库查询,返回DataSet对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <returns>DataSet对象</returns>        public static DataSet ExecuteDataSet(string connectionString, string commandText, CommandType commandType)        {            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            DataSet ds = new DataSet();            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand();            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, commandType, commandText);            try            {                SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);                sda.Fill(ds);            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (con != null)                {                    if (con.State == ConnectionState.Open)                    {                        con.Close();                    }                }            }            return ds;        }        /// <summary>        /// 执行数据库查询,返回DataSet对象        /// </summary>        /// <param name="connectionString">连接字符串</param>        /// <param name="commandText">执行语句或存储过程名</param>        /// <param name="commandType">执行类型</param>        /// <param name="cmdParms">SQL参数对象</param>        /// <returns>DataSet对象</returns>        public static DataSet ExecuteDataSet(string connectionString, string commandText, CommandType commandType, params SQLiteParameter[] cmdParms)        {            if (connectionString == null || connectionString.Length == 0)                throw new ArgumentNullException("connectionString");            if (commandText == null || commandText.Length == 0)                throw new ArgumentNullException("commandText");            DataSet ds = new DataSet();            SQLiteConnection con = new SQLiteConnection(connectionString);            SQLiteCommand cmd = new SQLiteCommand();            SQLiteTransaction trans = null;            PrepareCommand(cmd, con, ref trans, false, commandType, commandText, cmdParms);            try            {                SQLiteDataAdapter sda = new SQLiteDataAdapter(cmd);                sda.Fill(ds);            }            catch (Exception ex)            {                throw ex;            }            finally            {                if (con != null)                {                    if (con.State == ConnectionState.Open)                    {                        con.Close();                    }                }            }            return ds;        }        #endregion        #region 通用分页查询方法        /// <summary>        /// 通用分页查询方法        /// </summary>        /// <param name="connString">连接字符串</param>        /// <param name="tableName">表名</param>        /// <param name="strColumns">查询字段名</param>        /// <param name="strWhere">where条件</param>        /// <param name="strOrder">排序条件</param>        /// <param name="pageSize">每页数据数量</param>        /// <param name="currentIndex">当前页数</param>        /// <param name="recordOut">数据总量</param>        /// <returns>DataTable数据表</returns>        public static DataTable SelectPaging(string connString, string tableName, string strColumns, string strWhere, string strOrder, int pageSize, int currentIndex, out int recordOut)        {            DataTable dt = new DataTable();            recordOut = Convert.ToInt32(ExecuteScalar(connString, "select count(*) from " + tableName, CommandType.Text));            string pagingTemplate = "select {0} from {1} where {2} order by {3} limit {4} offset {5} ";            int offsetCount = (currentIndex - 1) * pageSize;            string commandText = String.Format(pagingTemplate, strColumns, tableName, strWhere, strOrder, pageSize.ToString(), offsetCount.ToString());            using (DbDataReader reader = ExecuteReader(connString, commandText, CommandType.Text))            {                if (reader != null)                {                    dt.Load(reader);                }            }            return dt;        }        #endregion        #region  预处理Command对象,数据库链接,事务,需要执行的对象,参数等的初始化        /// <summary>        /// 预处理Command对象,数据库链接,事务,需要执行的对象,参数等的初始化        /// </summary>        /// <param name="cmd">Command对象</param>        /// <param name="conn">Connection对象</param>        /// <param name="trans">Transcation对象</param>        /// <param name="useTrans">是否使用事务</param>        /// <param name="cmdType">SQL字符串执行类型</param>        /// <param name="cmdText">SQL Text</param>        /// <param name="cmdParms">SQLiteParameters to use in the command</param>        private static void PrepareCommand(SQLiteCommand cmd, SQLiteConnection conn, ref SQLiteTransaction trans, bool useTrans, CommandType cmdType, string cmdText, params SQLiteParameter[] cmdParms)        {            if (conn.State != ConnectionState.Open)                conn.Open();            cmd.Connection = conn;            cmd.CommandText = cmdText;            if (useTrans)            {                trans = conn.BeginTransaction(IsolationLevel.ReadCommitted);                cmd.Transaction = trans;            }            cmd.CommandType = cmdType;            if (cmdParms != null)            {                foreach (SQLiteParameter parm in cmdParms)                    cmd.Parameters.Add(parm);            }        }        #endregion    }

使用demo:

 /// <summary>        /// 获取数据库关键字信息        /// </summary>        /// <param name="category">分类</param>        /// <param name="versions">版本</param>        /// <returns></returns>        private DataSet GetSystemDataBaseKeyWords(string category, string versions)        {            StringBuilder sql = new StringBuilder();            sql.Append("SELECT Keywords , Versions , Type , Description , Category  , Id , Extends ");            sql.Append(" FROM A_DataBaseKeyWords ");            sql.AppendFormat(" WHERE 1={0} ", "1");            if (!String.IsNullOrEmpty(category))            {                sql.AppendFormat(" AND Category='{0}'", category);            }            if (!String.IsNullOrEmpty(versions))            {                sql.AppendFormat(" AND Versions='{0}'", versions);            }            return SQLiteHelper.ExecuteDataSet(SQLiteHelper.LocalDbConnectionString, sql.ToString(), CommandType.Text);        }

小注:

为了屏蔽32与64位系统问题,请使用改SQLite的dll,下载地址:点击打开链接

作者:jiankunking 出处:http://blog.csdn.net/jiankunking