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(" {0} {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(" {0} {1}", myReader.GetInt32(0), myReader.GetString(1));
    }

    myReader.Close();
    nwindConn.Close();
  }
}

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