asp.net中静态的类和成员函数都是静态的

using System;
using System.Collections.Generic;
//using System.Linq;
using System.Web;
using System.Data.OleDb;
using System.Data;

namespace Sophie
{
    /// <summary>
    /// db 的摘要说明。
    /// </summary>
    public class db
    {
        public db()
        {
        }
        /// <summary>
        /// 创造一个数据库连接函数
        /// ex:CreateConnetion()
        /// </summary>
        /// <returns>返回一个数据库连接对象</returns>

        private static OleDbConnection CreateConnection()
        {
            string databasestr = System.Configuration.ConfigurationSettings.AppSettings["connstr"];
            string constr;
            constr = "provider=Microsoft.Jet.OleDb.4.0;data source="
                + System.Web.HttpContext.Current.Server.MapPath(@databasestr);
            OleDbConnection con = new OleDbConnection(constr);
            return con;
        }

        /// </summary>
        /// 构造一个通用的OleDbParameter
        /// ex:PrepareCommand(new OleDbparameter("@me","你们好"),true,sqlstr,conn)
        /// <param name="conn">数据库连接对象</param>
        /// <param name="sqlstr">sql操作字符串</param>
        /// <param name="typed">是否使用OleDbParameters的参数数据</param>
        /// <param name="parm">OleDbParameters的参数娄组</param>
        /// <returns>返回一个数据库操作对象</returns>

        private static OleDbCommand PrepareCommand(OleDbConnection conn, string sqlstr, bool typed, OleDbParameter[] parm)
        {
            if (conn.State != ConnectionState.Open)
            {
                conn.Open();
            }
            OleDbCommand com = new OleDbCommand("", conn);

            com.CommandText = sqlstr;
            if (typed)
            {
                foreach (OleDbParameter parmitem in parm)
                {
                    com.Parameters.Add(parmitem);
                }
            }
            return com;
        }

        /// <summary>
        /// 返回查询数据的第一行第一列
        /// </summary>
        /// <param name="conn">同上</param>
        /// <param name="sqlstr">同上</param>
        /// <param name="typed">同上</param>
        /// <param name="parm">同上</param>
        /// <returns>返回一个object对象</returns>
        public static object ExecuteScalar(string sqlstr, OleDbParameter[] parm)
        {

            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, true, parm);
            object show = com.ExecuteScalar();

            conn.Close();
            com.Parameters.Clear();
            return show;
        }

        public static object ExecuteScalar(string sqlstr)
        {

            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, false, null);
            object show = com.ExecuteScalar();

            conn.Close();
            com.Parameters.Clear();
            return show;
        }

        /// <summary>
        /// </summary>
        /// <param name="conn">同上</param>
        /// <param name="sqlstr">同上</param>
        /// <param name="typed">同上</param>
        /// <param name="parm">同上</param>
        /// <returns>返回受影响的行数</returns>
        public static int ExecuteNonQuery(string sqlstr, OleDbParameter[] parm)
        {
            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, true, parm);
            int show = com.ExecuteNonQuery();

            conn.Close();
            com.Parameters.Clear();
            return show;
        }

        public static int ExecuteNonQuery(string sqlstr)
        {
            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, false, null);
            int show = com.ExecuteNonQuery();

            conn.Close();
            com.Parameters.Clear();
            return show;
        }
        /// <summary>
        /// 构造一个datareader的函数
        /// </summary>
        /// <param name="conn">同上</param>
        /// <param name="sqlstr">同上</param>
        /// <param name="typed">同上</param>
        /// <param name="parm">同上</param>
        /// <returns>返回一个向前读的流的对象OleDbDataReader</returns>
        public static OleDbDataReader ExecuteDataReader(string sqlstr, OleDbParameter[] parm)
        {
            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, true, parm);
            OleDbDataReader dr = com.ExecuteReader(CommandBehavior.CloseConnection);
            return dr;
        }

        public static OleDbDataReader ExecuteDataReader(string sqlstr)
        {
            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, false, null);
            OleDbDataReader dr = com.ExecuteReader(CommandBehavior.CloseConnection);
            com.Parameters.Clear();
            return dr;
        }

        /// <summary>
        /// 构造一个dataview的函数
        /// </summary>
        /// <param name="sqlstr">同上</param>
        /// <param name="typed">同上</param>
        /// <param name="parm">同上</param>
        /// <returns>返回一个dataview的对象</returns>
        public static DataView ExecuteDataview(string sqlstr, OleDbParameter[] parm)
        {

            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, true, parm);
            OleDbDataAdapter pter = new OleDbDataAdapter(com);
            DataSet ds = new DataSet();
            pter.Fill(ds, "datasource");
            DataView dataShow = ds.Tables["datasource"].DefaultView;
            conn.Close();
            com.Parameters.Clear();
            return dataShow;

        }

        public static DataView ExecuteDataview(string sqlstr)
        {

            OleDbConnection conn = CreateConnection();
            OleDbCommand com = PrepareCommand(conn, sqlstr, false, null);
            OleDbDataAdapter pter = new OleDbDataAdapter(com);
            DataSet ds = new DataSet();
            pter.Fill(ds, "datasource");
            DataView dataShow = ds.Tables["datasource"].DefaultView;
            conn.Close();
            com.Parameters.Clear();
            return dataShow;

        }
    }
   
}