Protected Sub button1_Click(sender As Object, e As System.EventArgs)
    Dim myStream As Stream
    Dim openFileDialog1 As New OpenFileDialog()
       
    openFileDialog1.InitialDirectory = "c:\"
    openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
    openFileDialog1.FilterIndex =  2 
    openFileDialog1.RestoreDirectory = True
       
    If openFileDialog1.ShowDialog() = DialogResult.OK Then
        myStream = openFileDialog1.OpenFile()
        If Not (myStream Is Nothing) Then
            ' Code to read the stream would go here.
            myStream.Close()
        End If
    End If
End Sub