Community Building and User Generated Content Forum

[youtube.com...]

The BBcode setup in the control panel would look something like this:

[youtube]http://www.youtube.com/watch?v={SIMPLETEXT}[/youtube]

The URL when posted would first have to start with:

[youtube.com...]

{SIMPLETEXT} only allows for "Characters from the latin alphabet (A-Z), numbers, spaces, commas, dots, minus, plus, hyphen and underscore".

If the posted URL doesn't meet that criteria its rejected and parsed as plain text. If it does meet that criteria the second panel allows for replacement which in this case would be the HTML provided by youtube (note I shortened it to keep it simple):

<object width="300" height="200"><param name="movie" value="http://www.youtube.com/v/{SIMPLETEXT}"></object>

The only input you're using from the user is the {SIMPLETEXT} which can only contain the values I listed above. How other forums handle it I don't know and they may require modification.