ASP.NET Cookie Expires value resets on Response.Redirect?

Question

I have a script that reads a form and puts some info into a cookie:

Dim oCookie as HttpCookie
oCookie = New HttpCookie("authInfo")
Select Case oResult
Case "No ClientID", "No Password", "No PracType", "No Encrypt", "CRC Mismatch"
    oCookie.Values.Add("LoggedIn", "False")
    oCookie.Values.Add("OnSupport", "False")
Case "Client Can Update"
    oCookie.Values.Add("LoggedIn", "True")
    oCookie.Values.Add("OnSupport", "True")
Case "Client Cannot Update"
    oCookie.Values.Add("LoggedIn", "True")
    oCookie.Values.Add("OnSupport", "False")
End Select
oCookie.Expires = DateTime.Now.AddHours(2)
HttpContext.Current.Response.Cookies.Add(oCookie)
HttpContext.Current.Response.Redirect("default.aspx")

The time is properly set right before it redirects, but when I try to print out that value this way (I have also tried Dim oCol as HttpCookieCollection = Request.Cookies, but I get the same result):

Response.Output.WriteLine(Request.Cookies("authInfo").Expires.ToString)

The time is always reset "01/01/0001 12:00:00 AM". Am I missing something that prevents the cookie from holding its Expires value?

Answer 1

Request.Cookies and Response.Cookies and use of the common cookie object makes of an intuative idiom but in fact a Request cookie and a Response cooke are quite different.

When you assign a Cookie in the response a Set-Cookie header gets added to the output and that will contain not only the value but also the path and the expiries value.

However when the browser sends the cookie back to the server in another request it simply includes the cookie name and value. It does not send path or expires info.

Hence these properties are meaningless when using the Request.Cookies collection.

Answer 2

I ran into such an issue when the initial request came from a different domain.
make sure you also add the domain for the cookie.

Answer 3

If you want to check for the expiration date you can add it to the cookie value collection. Then retrieve it and do the check.