ADO.NET 2.0 Dataset和Datatable 新功能新特性

发布时间：2020-05-22 11:49:02 所属栏目：asp.Net 来源：互联网

导读：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; d

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 XMLStreamReader 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 Mergestring 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 DataReaderstring 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;

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