How to setup an anti-spam button?

[buzincarl]

Hey Im looking to setup an anti-spam code / confirmation code for my download button, this way less people are spamming the site :P,

I wanted to setup a simple 3 digit code, a random code would appear(numbers),

Download button:

<center><input name='Submit' type='image' src='download.jpg' value='Submit' /></center>

[SmC]

Well you could always do something in PHP or Javascript, making the user enter the code before download will progress. In the intrest of saving time and bandwidth I'd recommend the JS approach.

[mikeyp]

Would you be looking for something like this?

http://www.modernbluedesign.com/web-design-blog/fighting-spam-with-css/