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();

}

}

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