c# - Delete 2 cookies with the same key and value

Question

*I know there are several questions regarding deleting a cookie here. I'm asking why I can't delete 2 cookies with the same key and value.

• The goal:

I'm working on a web application that has tons of legacy code, and in some cases, clients receive 2 cookies with the same key, value but the domain is different: one is explicit and the other is not (with and without dot notation aka .domain.com, domain.com). I need to delete both of those cookies.

• The problem:

Only one of the cookies is being deleted. The cookie is set from an ASP.NET application and the (.net core 2.1) API re-uses it. The API is a subdomain of the ASP.NET application, and the UI part is another subdomain.

• What eventually worked for me, is deleting all of the cookies:

   

    private void DeleteCookiesOnUnauthorizedResponse(HttpContext context)
            {
                var domain = new Uri(SOME_ENV_VARIABLE).Host;
    
                var options = GenerateExpiredCookieOptions(domain);
                var optionsWithDot = GenerateExpiredCookieOptions('.' + domain);
    
                var cookieList = context.Request.Cookies.ToList();
    
                foreach (var cookie in cookieList)
                {
                    context.Response.Cookies.Delete(cookie.Key, options);
                    context.Response.Cookies.Delete(cookie.Key, optionsWithDot);
                }
            }

     private CookieOptions GenerateExpiredCookieOptions(string domain)
            {
                return new CookieOptions
                {
                    Domain = domain,
                    Expires = DateTime.Now.AddMonths(-2),
                    IsEssential = true,
                    HttpOnly = true,
                    Secure = true,
                    Path = "/",
                    SameSite = SameSiteMode.Lax,
                };
            }

• What didn't work:

  The old fashion way of deleting a cookie

context.Response.Cookies.Append(someKey, string.Empty, optionsWithExpiredDate);

context.Response.Cookies.Delete(someKey);

Using a loop to delete only what I need didn't work either:

    foreach (var cookie in cookieList)
    {
          if(cookie.key == "myKey"){
                    context.Response.Cookies.Delete(cookie.Key, options);
                    context.Response.Cookies.Delete(cookie.Key, optionsWithDot);
           }
    }

Both of the cookies were sent to the browser as seen in the network tab, but only one of them got deleted.

• The question:

  Why? I don't want to delete all of the cookies, just those 2, but one of them appears to be indestructible.

Answer 1

等待大神答复