数据库操作笔记

操作Access数据库

OleDbConnection用法

            string strConn = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=testDB.accdb";
            OleDbConnection conn = new OleDbConnection(strConn);
            conn.Open();//打开
            //conn.Close();//关闭

       //打开数据连接
        public static OleDbConnection OpenConnection()
        {
            OleDbConnection conn = new OleDbConnection(strConn);
            try
            {
                conn.Open();
            }
            catch(Exception ex)
            {
                Console.WriteLine("打开数据库异常：{0}",ex.Message);
            }

            return conn;
        }

OleDbCommand用法

        //执行SQL语句，并返回受影响的行数
        public static int ExecuteNonQuery(string strCmd)
        {
            int rows = 0;
            OleDbConnection conn = OpenConnection();
            if(conn.State == System.Data.ConnectionState.Open)
            {
                try
                {
                    OleDbCommand comm = new OleDbCommand(strCmd, conn);
                    rows = comm.ExecuteNonQuery();//返回受影响的行数
                }
                catch (Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
                finally
                {
                    conn.Close();
                }
            }

            return rows;
        }

        //执行SQL语句，并返回受影响的行数
        //传递参数
        public static int ExecuteNonQuery(string strCmd, OleDbParameter[] values)
        {
            int rows = 0;
            OleDbConnection conn = OpenConnection();
            if(conn.State == System.Data.ConnectionState.Open)
            {
                try
                {
                    OleDbCommand cmd = new OleDbCommand(strCmd, conn);
                    cmd.Parameters.AddRange(values);
                    rows = cmd.ExecuteNonQuery();
                }
                catch(Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
                finally
                {
                    conn.Close();
                }
            }

            return rows;
        }

DataTable用法

       //获取数据表
        public static DataTable GetDataTable(string strCmd)
        {
            DataTable table = new DataTable();
            OleDbConnection conn = OpenConnection();
            if(conn.State == ConnectionState.Open)
            {
                try
                {
                    OleDbDataAdapter adapter = new OleDbDataAdapter(strCmd, conn);
                    adapter.Fill(table);
                }
                catch (Exception ex)
                {
                    Console.WriteLine("GetDataTable:" + ex.Message);
                }
                finally
                {
                    conn.Close();
                }
            }

            return table;
        }