Inserting standard values into the attribute_edit_gui

Monday 29 September 2008 2:10:41 am

I have this form where users can subscribe for an event.

I can get the user id with the following code:

{$current_user.contentobject_id}

Now what I want to do is have the user id filled in automatically when users click the subscribe button.
How do I do this?

thanks in advance.