asp.net简单数据工厂

using System;
using System.Data;
namespace Lem_DALFactory
{
    /// <summary>
    /// ICommandAccess 的摘要说明。
    /// </summary>
    public interface ICommonAccess
    {
        //传入增,删,改的SQL语句
        string GetExCmd(string strSql);

        //传入一条查询语句,和一个表名
        DataSet GetDs(string strSql,string TableName);

        //传入一个查询语句,返回首行首列,用于登陆
        int GetSearch(string strSql);
    }
}

using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
namespace Lem_DALFactory
{
    /// <summary>
    /// SqlProvider 的摘要说明。
    /// </summary>
    public class SqlProvider:ICommonAccess
    {
        SqlConnection conn=null;
        public SqlProvider()
        {
            conn=new SqlConnection(ConfigurationSettings.AppSettings["conn"]);
        }
        #region ICommandAccess 成员

        public string GetExCmd(string strSql)
        {
            SqlCommand cmd=new SqlCommand(strSql,conn);
            conn.Open();
            int i=cmd.ExecuteNonQuery();
            string str="";
            if(i>0)
            {
                str="操作成功";
            }
            else
            {
                str="操作失败";
            }
            return str;
        }

        public DataSet GetDs(string strSql,string TableName)
        {
            SqlDataAdapter da=new SqlDataAdapter(strSql,conn);
            DataSet ds=new DataSet();
            da.Fill(ds,TableName);
            return ds;
        }

        public int GetSearch(string strSql)
        {
            SqlCommand cmd=new SqlCommand(strSql,conn);
            conn.Open();
            int i=int.Parse(cmd.ExecuteScalar().ToString());
            return i;
        }

        #endregion
    }
}

using System;
using System.Data;
using System.Data.OleDb;
using System.Configuration;
namespace Lem_DALFactory
{
    /// <summary>
    /// OdbcProvider 的摘要说明。
    /// </summary>
    public class OleDbProvider:ICommonAccess
    {
        OleDbConnection conn=null;
        public OleDbProvider()
        {
            
            conn=new OleDbConnection(ConfigurationSettings.AppSettings["conn"]);
        }
        #region ICommonAccess 成员

        public string GetExCmd(string strSql)
        {
            OleDbCommand cmd=new OleDbCommand(strSql,conn);
            conn.Open();
            int i=cmd.ExecuteNonQuery();
            string str="";
            if(i>0)
            {
                str="操作成功";
            }
            else
            {
                str="操作失败";
            }
            return str;
        }

        public System.Data.DataSet GetDs(string strSql, string TableName)
        {
            OleDbDataAdapter da=new OleDbDataAdapter(strSql,conn);
            DataSet ds=new DataSet();
            da.Fill(ds,TableName);
            return ds;
        }

        public int GetSearch(string strSql)
        {
            OleDbCommand cmd=new OleDbCommand(strSql,conn);
            conn.Open();
            int i=int.Parse(cmd.ExecuteScalar().ToString());
            return i;
        }

        #endregion
    }
}

using System;
using System.Configuration;
using System.Reflection;
namespace Lem_DALFactory
{
    /// <summary>
    /// DataFactory 的摘要说明。
    /// </summary>
    public class DataFactory
    {
        public static ICommonAccess GetCommonAccess()
        {
            string path=ConfigurationSettings.AppSettings["provider"];
            ICommonAccess CommonAccess=(ICommonAccess)Assembly.Load("Lem_DALFactory").CreateInstance("Lem_DALFactory."+path);

            return CommonAccess;
        }
    }
}