Trouble setting a Cookie

I want to check for a cookie and set it if it does not exist.

The only Trigger options I have are:

Any form post
Before Page Load
Current page submit
Button Submit pressed

I'm trying to catch the referrer, so none of these will work because it will change with every single page load.

Forgot to post the code I am using:
<?php
if ("" == "") {
setcookie("Referrer", "".((isset($_SERVER["HTTP_REFERER"]))?$_SERVER["HTTP_REFERER"]:"") ."", time()+(60*60*24*30), "/", "", 0);
}
?>

I know I just need something in the if (""=="") spot but I am not familiar enough with php yet to figure it out.

That is an editable list, so you can use a custom trigger to be whatever you want. Just design it so that the value you enter for the trigger is empty if you don't want it to fire.

Describe when exactly you would want to set it? Only if it isn't already set? Only for a specific referrer?

I want it set on the first visit to the site, and to remain persistent from page to page and on subsequent visits for 30 days.

thanks,
Bart

Then use the trigger:

<?php echo(isset($_COOKIE['Referrer'])?$_COOKIE['Referrer']:""); ?>

it would add code like:
if ((isset($_COOKIE['Referrer'])?$_COOKIE['Referrer']:"") == "") {

which would only set the cookie if it didn't already exist and it looks like you are already setting it for 30 days.

Thank you, I'm sure that will work fine.
I was just struggling with syntax.

Is this something that could be added in a future rev? Seems like this is a pretty common use of cookies and it is included in the choices for setting a Session value.

It is a possible addition... we do have the equivalent for session variables so it would seem logical. However as far as I know you are the first to ask for it, so either people aren't doing it as often as you think or the feature may not be necessary since they are figuring it out on their own.

We could address it, but their might be bigger fish to fry.

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