Private Sub ReadGetOrdinal(ByVal connectionString As String)
    Dim queryString As String = _
       "SELECT DISTINCT CustomerID FROM dbo.Orders;"

    Using connection As New SqlConnection(connectionString)
        Dim command As New SqlCommand(queryString, connection)
        connection.Open()

        Dim reader As SqlDataReader = command.ExecuteReader()

        ' Call GetOrdinal and assign value to variable.
        Dim customerID As Integer = reader.GetOrdinal("CustomerID")

        ' Use variable with GetString inside of loop.
        While reader.Read()
            Console.WriteLine("CustomerID={0}", reader.GetString(customerID))
        End While

        ' Call Close when done reading.
        reader.Close()
    End Using
End Sub

' 导入命名空间
Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Xml
Imports System.Windows.Forms
Imports System.Data.SqlClient


Public Class MainClass
    Shared Dim WithEvents con As SqlConnection

    Shared Sub Main()
        con = New SqlConnection("Server=(local)\SQLEXPRESS;Initial Catalog=MyDatabase;Integrated Security=SSPI") 

        Dim cmd As New SqlCommand()

        cmd.CommandText = "SELECT * FROM Employee"
        cmd.Connection = con

        Try
            con.Open()
            Dim reader As SqlDataReader = cmd.ExecuteReader()
            Dim OrderIDIdx As Integer = reader.GetOrdinal("ID")
            'Dim OrderDateIdx As Integer = reader.GetOrdinal("FirstName")
            'Dim OrderFreightIdx As Integer = reader.GetOrdinal("LastName")

            Do
                While reader.Read()
                    Dim OrderID As Integer = reader.GetInt32(OrderIDIdx)
                    'Dim OrderDate As DateTime = reader.GetDateTime(OrderDateIdx)
                    'Dim OrderFreight As Decimal = reader.GetDecimal(OrderFreightIdx)

                    'Console.WriteLine(OrderID & vbTab & OrderDate & vbTab & OrderFreight)
                    Console.WriteLine(OrderID & vbTab )
                End While
            Loop While reader.NextResult()

            reader.Close()
        Finally
            con.Close()
        End Try
    End Sub
End Class