title: cancel throws error in OpenFileDialog box
body: <p>I'm trying to implement an OpenFileDialog box, its works fine except if I choose to click cancel then program throws an error, saying that file can't be found, which confuses me cause I didnt select a file.</p>
  
  <p>The following is the code. how I can implement the cancel button?</p>
  
  <pre><code>OpenFileDialog1.InitialDirectory = "C:\"
  OpenFileDialog1.FileName = "Select a Batch file..."
  OpenFileDialog1.Filter = "Batch files (*.bat) | *.bat"
  OpenFileDialog1.ShowDialog()
  
  If OpenFileDialog1.ShowDialog = Windows.Forms.DialogResult.Cancel Then
      OpenFileDialog1.Dispose()
  End If
  
  Dim R As New IO.StreamReader(OpenFileDialog1.FileName)
  TextBox4.Text = R.ReadToEnd
  R.Close()
  
  Button4.Enabled = True
  Button6.Enabled = True
  </code></pre>