Similar to the OldDbCommand object, you create Sql and ODBC Command objects by using SqlCommand and OdbcCommand classes. You can pass the same arguments as discussed previously. The only difference is the connection string. For Example, listing 5-31 uses SqlCommand and SqlConnection to connect to SQL server database. As you can see from listing 5-31, the only changes are the class prefixes and the connection string. Similarly, you can use the OdbcCommand object.
Listing 5-31. Using SqlCommand to access a SQL Server database
Imports System
Imports System.Collections.Generic
Imports System.Text
Imports System.Data.SqlClient
Namespace ConsoleApplication1
Class Program
Private Shared Sub Main(ByVal args As String())
' Connection and SQL strings
Dim SQL As String = "SELECT * FROM Orders"
' create a connection object
Dim ConnectionString As String = "Integrated security =SSPI;" & "Initial Catalog = Northwind;" & "Data Source = MAIN-SERVER; "
Dim conn As New SqlConnection(ConnectionString)
' create command object
Dim cmd As New SqlCommand(SQL, conn)
' open connection
conn.Open()
' call command's ExcuteReader
Dim reader As SqlDataReader = cmd.ExecuteReader()
Try
While reader.Read()
Console.Write("OrderID:" & reader.GetInt32(0).ToString())
Console.Write(" ,")
Console.WriteLine("Customer : " & reader.GetString(1).ToString())
End While
Finally
' close reader and connection
reader.Close()
conn.Close()
End Try
End Sub
End Class
End Namespace
The output of Listing 5-31 looks Figure 5-31.
Figure 5-31. Output of listing 5-31
Conclusion
Hope this article would have helped you in understanding Creating Sql and ODBC Command Objects in ADO.NET. See my other articles on the website on ADO.NET.