>I have a URL field bound to a textbox on a form. Next to the textbox is a button that will open IE; or whatever the registered browser is; and navigate to the URL in the textbox.
>
>The users have found out that they can enter local addresses (c:\ or \\computername\c:) and be able to browse them. My client does not like this!
>
>They want me to block navigating to any URL that is not http protocol. Is there any way to do this other than forcing them to put 'http://' at the beginning of the URL?
>
>What I'm looking for is a function that will take a string and return a True if it is http and False if not. Does anything like this exist?

Dan,

Before you work this out, how to prevent your users anyhow from typing such an "URL" once in IE (or whatever) ? I mean, if THAT can't be done (can it ?), don't bother this I'd say ...