ASP是什么,ASP开发

侯绮琴

The following example shows what a simple ADO.NET application that connects to the Northwind database and returns a list of Categories would look like. The example writes the output to the console, or command prompt.  The following example shows what a simple ADO.NET application that connects to the Northwind database and returns a list of Categories. The example writes the output to the console, or command prompt.  SqlClient  [Visual Basic]  Imports System  Imports System.Data  Imports System.Data.SqlClient  Imports Microsoft.VisualBasic  Public Class Sample  Public Shared Sub Main()  Dim nwindConn As SqlConnection = New SqlConnection(Data Source=localhost; _  User Id=sa;Password=pwd;Initial Catalog=northwind)  Dim catCMD As SqlCommand = nwindConn.CreateCommand()  catCMD.CommandText = SELECT CategoryID, CategoryName FROM Categories  nwindConn.Open()  Dim myReader As SqlDataReader = catCMD.ExecuteReader()  Do While myReader.Read()  Console.WriteLine(vbTab {0} vbTab {1}, myReader.GetInt32(0), myReader.GetString(1))  Loop  myReader.Close()  nwindConn.Close()  End Sub  End Class  [C#]  using System;  using System.Data;  using System.Data.SqlClient;  class Sample  {  public static void Main()  {  SqlConnection nwindConn = new SqlConnection(Data Source=localhost;User Id=sa;Password=pwd;Initial Catalog=northwind);  SqlCommand catCMD = nwindConn.CreateCommand();  catCMD.CommandText = SELECT CategoryID, CategoryName FROM Categories;  nwindConn.Open();  SqlDataReader myReader = catCMD.ExecuteReader();  while (myReader.Read())  {  Console.WriteLine(t{0}t{1}, myReader.GetInt32(0), myReader.GetString(1));  }  myReader.Close();  nwindConn.Close();  }  }  OleDb  [Visual Basic]  Imports System  Imports System.Data  Imports System.Data.OleDb  Imports Microsoft.VisualBasic  Public Class Sample  Public Shared Sub Main()  Dim nwindConn As OleDbConnection = New OleDbConnection(Provider=SQLOLEDB;Data Source=localhost; _  User Id=sa;Password=pwd;Initial Catalog=northwind)  Dim catCMD As OleDbCommand = nwindConn.CreateCommand()  catCMD.CommandText = SELECT CategoryID, CategoryName FROM Categories  nwindConn.Open()  Dim myReader As OleDbDataReader = catCMD.ExecuteReader()  Do While myReader.Read()  Console.WriteLine(vbTab {0} vbTab {1}, myReader.GetInt32(0), myReader.GetString(1))  Loop  myReader.Close()  nwindConn.Close()  End Sub  End Class  [C#]  using System;  using System.Data;  using System.Data.OleDb;  class Sample  {  public static void Main()  {  OleDbConnection nwindConn = new OleDbConnection(Provider=SQLOLEDB;Data Source=localhost;User Id=sa;Password=pwd;Initial Catalog=northwind);  OleDbCommand catCMD = nwindConn.CreateCommand();  catCMD.CommandText = SELECT CategoryID, CategoryName FROM Categories;  nwindConn.Open();  OleDbDataReader myReader = catCMD.ExecuteReader();  while (myReader.Read())  {  Console.WriteLine(t{0}t{1}, myReader.GetInt32(0), myReader.GetString(1));  }  myReader.Close();  nwindConn.Close();  }  }