DBHelper

 

  /// <summary>
        /// 根据sql 返回受影响的行数（增删改）
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static int ExecuteSql(string sql)
        {
            int rs = 0;
            using (SqlConnection conn = new SqlConnection(connString))
            {
                conn.Open();
                try
                {
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    rs = cmd.ExecuteNonQuery();
                    return rs;
                }
                catch (Exception ex)
                {
                    throw new Exception(ex.Message.ToString());
                }
            }
        }
        /// <summary>
        /// 根据sql语句和参数执行sql
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="parmas"></param>
        /// <returns></returns>
        public static int ExecuteSql(string sql, SqlParameter[] param)
        {
            try
            {
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    conn.Open();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    cmd.Parameters.Add(param);
                    return cmd.ExecuteNonQuery();
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message.ToString());
            }
        }
        /// <summary>
        /// 根据sql 返回datatable
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static DataTable QueryBySql(string sql)
        {
            try
            {
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    DataSet ds = new DataSet();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    SqlDataAdapter adp = new SqlDataAdapter(cmd);
                    adp.Fill(ds);
                    return ds.Tables[0];
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message.ToString());
            }
        }
        /// <summary>
        /// 根据sql 返回datatable
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public static DataTable QueryBySql(string sql, SqlParameter[] param)
        {
            try
            {
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    DataSet ds = new DataSet();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    cmd.Parameters.Add(param);
                    SqlDataAdapter adp = new SqlDataAdapter(cmd);
                    adp.Fill(ds);
                    return ds.Tables[0];
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message.ToString());
            }

        }
        /// <summary>
        /// 根据sql语句返回查询结果的首行首列
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sql)
        {
            using (SqlConnection conn = new SqlConnection(connString))
            {
                conn.Open();
                try
                {
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    return cmd.ExecuteScalar();
                }
                catch (Exception ex)
                {
                    throw new Exception(ex.Message.ToString());
                }
            }
        }
        /// <summary>
        /// 根据sql语句返回查询结果的首行首列
        /// </summary>
        /// <param name="sql"></param>
        /// <returns></returns>
        public static object ExecuteScalar(string sql, SqlParameter[] param)
        {
            using (SqlConnection conn = new SqlConnection(connString))
            {
                conn.Open();
                try
                {
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    cmd.Parameters.Add(param);
                    return cmd.ExecuteScalar();
                }
                catch (Exception ex)
                {
                    throw new Exception(ex.Message.ToString());
                }
            }
        }
        /// <summary>
        /// 返回datareader
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public static SqlDataReader ExecuteReader(string sql)
        {
            try
            {
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    conn.Open();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    return cmd.ExecuteReader(CommandBehavior.CloseConnection);
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message.ToString());
            }
        }
        /// <summary>
        /// 返回datareader
        /// </summary>
        /// <param name="sql"></param>
        /// <param name="param"></param>
        /// <returns></returns>
        public static SqlDataReader ExecuteReader(string sql, SqlParameter[] param)
        {
            try
            {
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    conn.Open();
                    SqlCommand cmd = new SqlCommand(sql, conn);
                    cmd.Parameters.Add(param);
                    return cmd.ExecuteReader(CommandBehavior.CloseConnection);
                }
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message.ToString());
            }
        }