Why can't I delete this cookie?

Question

Okay, here is the 411 - I have the following event handler in my Global.asax.cs file:

private void Global_PostRequestHandlerExecute(object sender, EventArgs e)
{
   if (/* logic that determines that this is an ajax call */)
   {
      // we want to set a cookie
      Response.Cookies.Add(new HttpCookie("MyCookie", "true"));
   }
}

That handler will run during Ajax requests (as a result of the Ajax framework I am using), as well as at other times - the condition of the if statement filters out non-Ajax events, and works just fine (it isn't relevant here, so I didn't include it for brevity's sake).

It suffices us to say that this works just fine - the cookie is set, I am able to read it on the client, and all is well up to that point.

Now for the part that drives me nuts.

Here is the JavaScript function I am using to delete the cookie:

function deleteCookie(name) {
   var cookieDate = new Date();
   cookieDate.setTime(cookieDate.getTime() - 1);
   document.cookie = (name + "=; expires=" + cookieDate.toGMTString());
}

So, of course, at some point after the cookie is set, I delete it like so:

deleteCookie("MyCookie");

Only, that doesn't do the job; the cookie still exists. So, anyone know why?

Answer 1

you have to delete your cookie at the same path where you created it. so create your cookie with path=/ and delte it with path=/ as well..

Answer 2

• Have you checked the client-side and server-side cookie domains and paths to ensure they're the same?
• Is one cookie secure and the other not?
• Other than that, I would suspect server/client clock sync issues, as Erlend suggests.