Question

I’m not sure what is happening here but sometimes I get an error message “Server cannot modify cookies after HTTP headers have been sent” when trying to set cookies. From what I can tell it is mostly search bots of some sort. Do bots have cookies disabled or something? I can’t reproduce it when I disable cookies. My code below is ran in the controller. Does it look correct?

                var cookie = new HttpCookie(Config.ApiCookie)
                {
                    HttpOnly = true,
                    Secure = false,
                    Value = authenticationResponse[SessionKey].ToString()
                };

                if (HttpContext.Current.Response.Cookies[Config.ApiCookie] != null)
                {
                    HttpContext.Current.Response.Cookies.Set(cookie);
                }
                else
                {
                    HttpContext.Current.Response.Cookies.Add(cookie);
                }

Answer 1

The problem was with the .Set which is buggy. I used the code below instead and fixed the issue.

if (HttpContext.Current.Response.Cookies[Config.ApiCookie] != null)
            {
                HttpContext.Current.Response.Cookies[Config.ApiCookie].Value = cookie.Value;
            }
            else
            {
                HttpContext.Current.Response.Cookies.Add(cookie);
            }