if (openFileDialog1.ShowDialog() == true)
{
    // Open the selected file to read.
    System.IO.Stream fileStream = openFileDialog1.SelectedFile.OpenRead();

    using (System.IO.StreamReader reader = new System.IO.StreamReader(fileStream))
    {
        // Read the first line from the file and write it the textbox.
        tbResults.Text = reader.ReadLine();
    }
    fileStream.Close();
}

If (openFileDialog1.ShowDialog = True) Then
    'Open the selected file to read.
    Dim fileStream As System.IO.Stream = openFileDialog1.SelectedFile.OpenRead

    Using reader As New System.IO.StreamReader(fileStream)
        ' Read the first line from the file and write it to the text box.
        tbResults.Text = reader.ReadLine
    End Using
    fileStream.Close()
End If