Question

I simply try to set cookie when form is submitted but it seems that the function sets
cookie on every refresh of page

function Sub(){
var exdays="3000";
var value="asdf";
var exdate=new Date();
var c_name="asdf";
exdate.setDate(exdate.getDate() + exdays);
var c_value=escape(value) + ((exdays==null) ? "" : "; expires="+exdate.toUTCString());
document.cookie=c_name + "=" + c_value;

alert("asdf"); //just for debugging
return true; }
</SCRIPT>

<form id="myform" action="http://localhost" onsubmit="return Sub();">

Answer 1

The cookie will be sent by the browser on each request for the same URL until it is deleted, it expires, or for session cookies, until a new session is created.

You’re setting an expiration, so it’s not a session cookie. So your browser will send the cookie on each page load to that URL, regardless of whether you clicked something or not.

Try removing the expiration date, clearing your cookie cache, and restarting your browser.

The cookie will not be present until you submit once. Then the cookie will be present until you close your session (restart the browser).