How to tell if on HTTPS vs HTTP

[workin4u]

Hi all.

Can anyone tell me how I can determine whether or not a user is viewing the pages through a secure (HTTPS) connection or not.

Thanks in advance.

[Weedpacket]

Look at the URL they're requesting and see if whether it uses the https: or http: scheme? That's the first idea that pops into my head.

[mtmosier]

if ($_SERVER['HTTPS'] == 'on') {