The Secure attribute accepts "true" or "false".  Secure="true" causes a target URL to be partially encoded when navigating to a webpage.

   <ActionLink Href="" Label="Brick River User's Guide" Secure="true" />

The code above places a link on the Action button for records opened from the View.  Secure="true" masks the portion of the URl following the domain name.

The link will display in the browser like this:!GN3A4Zof-9k96PXAEklhQLwj9hR6zaal7X4jKdJ4CiB