我的一亩三分地 我就喜欢!
13fen  设为主页
 收藏本站
 
当前位置: > 一亩三分地:首页 > 网络学院 > 网络编程 > net专区 > ADO.NET2.0Dataset和Datatable新功能新特性
热门文章排行
热门文章排行 检查email地址格式的代码(01-11)
PHP操作文件问答(01-11)
PHP安装攻略:安装并配置PHP(10-23)
PHP的十个高级技巧 4(10-23)
关于APE的介绍、播放及制作(03-22)
精采文章排行
精采文章排行 ASP.NET与MySQL数据库简明图示入门教(11-16)
ASP.NET与MySQL数据库简明图示入门教(11-16)
ASP.NET 链接数据库基础(11-16)
webconfig的设置节点说明(11-16)
部署ASP.NET的三大技术(上)(11-16)
技术专题推荐
网管论坛交流
 

ADO.NET2.0Dataset和Datatable新功能新特性 

作者:佚名   来源:Linux 宝库   点击:   日期:2006-12-22

1.新的索引引擎更快的执行效率
   下面这段代码在2003中需要157秒,在2005中只要11秒就可以完成:



DataSet ds = new DataSet();


            ds.Tables.Add("BigTable");
            ds.Tables[0].Columns.Add("ID", Type.GetType("System.Int32"));
            ds.Tables[0].Columns["ID"].Unique = true;
            ds.Tables[0].Columns.Add("Value", Type.GetType("System.Int32"));


            Cursor.Current = Cursors.WaitCursor;


            DateTime datBegin = DateTime.Now;


            Random rand = new Random();
            int i, intValue;
            DataRow dr;


            for (i = 1; i <= 500000; i++)
            {
                try
                {
                    intValue = rand.Next();


                    dr = ds.Tables[0].NewRow();


                    dr["ID"] = intValue;
                    dr["Value"] = intValue;


                    ds.Tables[0].Rows.Add(dr);
                }
                catch { }
            }


            Cursor.Current = Cursors.Default;


            MessageBox.Show("Elapsed Time: " + (DateTime.Now - datBegin).Seconds.ToString());
            MessageBox.Show("count = " + ds.Tables[0].Rows.Count.ToString());
2.Dataset可以序列化为二进制文件
 string connstr = "server=(local);database=northwind;integrated security=true;async=true";


            DataSet ds = new DataSet();
            SqlDataAdapter dadpt = new SqlDataAdapter("select * from [order details]", connstr);
            dadpt.Fill(ds);


            BinaryFormatter bf = new BinaryFormatter();
            FileStream fs = new FileStream(@"c:\xml1.txt",FileMode.OpenOrCreate);


            ds.RemotingFormat = SerializationFormat.Binary;


            bf.Serialize(fs,ds);     3.更独立的Datatable
  DataTable Write XML  string connstr = "server=(local);database=northwind;integrated security=true;async=true";
            SqlDataAdapter dadpt = new SqlDataAdapter("select * from [order details]", connstr);
            DataTable dt = new DataTable("Customer");
            dadpt.Fill(dt);


            dt.WriteXml(@"c:\DataTable.xml",true);
            dt.WriteXmlSchema(@"c:\DataTableSchema.xml");   DataTable Read XML
 StreamReader sr = new StreamReader(@"C:\DataTableSchema.xml");


            DataTable dt = new DataTable();
            dt.ReadXmlSchema(sr);


            dt.ReadXml(new StreamReader(@"c:\dataTable.xml"));


            this.dataGridView1.DataSource = dt;    DataTable Merge
 string connstr = "server=(local);database=northwind;integrated security=true;async=true";
            SqlDataAdapter dadpt = new SqlDataAdapter("select * from customers", connstr);
            DataTable dt = new DataTable("Customer");
            dadpt.Fill(dt);


            SqlDataAdapter dadpt1 = new SqlDataAdapter("select * from customers", connstr);
            DataTable dt1 = new DataTable("Customer1");
            dadpt1.Fill(dt1);


            dt.Merge(dt1);


            this.dataGridView1.DataSource = dt;  DataTable Load DataReader
 string connstr = "server=(local);database=northwind;integrated security=true;async=true";
            SqlConnection conn = new SqlConnection(connstr);
            conn.Open();
            SqlCommand cmd = new SqlCommand("select * from [order details]", conn);
            SqlDataReader dr = cmd.ExecuteReader();


            DataTable dt = new DataTable("Customer");
            dt.Load(dr);


            this.dataGridView1.DataSource = dt;







文章评论】 【收藏本文】 【推荐好友】 【打印本文】 【论坛讨论

   相关文章:
·给你的FileSystemObject对象加把锁 ·在 Web 页上使用条件数值格式
·连接数据库查询手册(不仅仅适用于asp) ·警惕"给你的FileSystemObject对象加把锁"
·用ASP做全文检索 ·如何把ASP编写成DLL

   文章评论:(条)
  
 请留名: 匿名评论   点击查看所有评论 网管论坛
 

  责任编辑:一分  声明:刊登此文章是为了传递更多信息,文章内容仅供参考,转载请注明出处。