采用泛型链接多类型数据库[含源码]

         最近在看vs2005上关于泛型的介绍，同时考虑到手头上使用的DBSERVICE库中文件过多（共7个CS文件），想利用泛型技术对它进行“瘦身”，最后系统只有2个文件。现把相关文件做一简单说明:

         说明：DbAccess.cs文件， InitailDB函数采用反射进行相关信息搜集      

 1 /**//// <summary>
 2        /// 初始化数据库信息
 3        /// </summary>
 4        /// <typeparam name="T"></typeparam>
 5        /// <param name="dai"></param>
 6        public static void InitailDB<T>(T dai)
 7        {
 8            Type type = dai.GetType();
 9            object[] args = null; 
10            concreteDbConn = (IDbConnection)type.GetMethod("CreateConnection").Invoke(dai, args);
11            concreteDbConn.ConnectionString = (string) type.GetMethod("GetConnectionString").Invoke(dai, args);
12            concreteDbConn.Open();
13            concreteDbCommand = (IDbCommand)type.GetMethod("CreateCommand").Invoke(dai, args);
14            concreteDbTrans = (IDbTransaction)type.GetMethod("CreateTransaction").Invoke(dai, new object[] { concreteDbConn });
15            concreteDbCommand.Connection = concreteDbConn;
16            concreteDbCommand.Transaction = concreteDbTrans;
17            concreteDbAdapter = (IDbDataAdapter)type.GetMethod("CreateDataAdapter").Invoke(dai, args);
18        }
19

       
   调用方法：CreateGenericInstance()，只要将相应的类型做为参数加入到InitailDB<T>中即可

    InitailDB<Generic_Access<SqlConnection, SqlCommand, SqlDataAdapter>>(
                            Generic_Access < SqlConnection, SqlCommand, SqlDataAdapter >.GetInstance());break;

    泛型类DB_Generic.cs代码如下 ：   

 using System;
    using System.Data;
    using System.Configuration;
    using System.Collections.Generic;

 public sealed class Generic_Access<Connection, Command, DataAdapter>
        where Connection : class, new()
        where Command : class, new()
        where DataAdapter : class, new()
     
    {

        public static volatile Generic_Access<Connection, Command, DataAdapter> singleFactory = null;

        private static object syncObj = new object();

        public static Generic_Access<Connection, Command, DataAdapter> GetInstance()
        {
            if (singleFactory == null)
            {
                lock (syncObj)
                {
                    if (singleFactory == null)
                    {
                        singleFactory = new Generic_Access<Connection, Command, DataAdapter>();
                    }
                }
            }
            return singleFactory;
        }


        private Generic_Access()
        {
        }


        public void Disponse()
        {
            singleFactory.Disponse();
        }
             
        /**//// <summary>
        /// 建立默认Connection对象
        /// </summary>
        /// <returns>Connection对象</returns>
        public Connection CreateConnection()
        {
            return new Connection();
              
        }

       
        /**//// <summary>
        /// 建立Command对象
        /// </summary>
        /// <returns>Command对象</returns>
        public Command CreateCommand()
        {
             return new Command();
        }


        /**//// <summary>
        /// 建立DataAdapter对象
        /// </summary>
        /// <returns>DataAdapter对象</returns>
        public DataAdapter CreateDataAdapter()
        {
              return new DataAdapter();
        }



        /**//// <summary>
        /// 根据Connection建立Transaction
        /// </summary>
        /// <param name="myDbConnection">Connection对象</param>
        /// <returns>Transaction对象</returns>
        public IDbTransaction CreateTransaction(IDbConnection myDbConnection)
        {
            return myDbConnection.BeginTransaction();
        }


        /**//// <summary>
        /// 根据Command建立DataReader
        /// </summary>
        /// <param name="myDbCommand">Command对象</param>
        /// <returns>DataReader对象</returns>
        public IDataReader CreateDataReader(IDbCommand myDbCommand)
        {
            return myDbCommand.ExecuteReader();
        }
.

最后是测试代码：using DB_Generic; 

 1public partial class DB_Generic_Default : System.Web.UI.Page
 2  {
 3    protected void Page_Load(object sender, EventArgs e)
 4    {
 5        if (!Page.IsPostBack)
 6        {
 7           
 8            Response.Write(DbAccess.SelectMaxID("users", "ID") + "<BR>");
 9
10            string sql = "Select top 10 * From users Order By id asc";
11            Repeater1.DataSource = DbAccess.SelectAllSqlString(sql).Tables[0].DefaultView;
12            Repeater1.DataBind();
13
14

.....

详情见 源代码

     谢谢大家！

     如须转载，请注明出处。