How to prevent swf files being downloaded

Question

People,
I'm a teacher and I have some animations made in flash language (swf). I would like to publish these animations on my web site so my students could see, but I wonder if there is any way to prevent these animations being downloaded.
Example: when I see an animation published on my web site, this animation is stored in Internet Temporary Files and I can save this animation anywhere. How can I prevent an animation is stored in the temporary folder? In other words, this animation can only be seen if the user is logged on the site.
Urgent!!!
Thanks.
Alyson

Answer 1

I think that's what I want. I found a site that has exactly what I need. It
is done this way too?
Plese take a look at http://www.edumedia-sciences.com/en/a559-scintigraphy
<http://www.edumedia-sciences.com/>
Thanks
2009/11/16 moccamaximum <[email protected]>
You could implement a kind of time-barrier, like in the trial versions you
download from softwarecompanys.
For the most users, that are not understanding actionscript and know how to
read the code, even if they decompile it, that would prevent the swf being
played after a certain date that you would have to implement in your code.
In AS2 the code would be like this:
>
var now:Date = new Date(); //reads the user system date
var release:Date = new Date(2009, 11, 16); //here goes the date, when you
want to have the program deactivated
>
if(now <= release){
   playSwf(); // here goes your normal code
>
else{
   doNothing();
>
Like the most TimeBarriers this could be easily circumvented if the user
sets back his system date, so do not give a message like "You trial period
has expired"
>