CookieContainer bug?

c#, cookiecontainer

Solution

I just found the fix for this bug and discussed here: http://dot-net-expertise.blogspot.com/2009/10/cookiecontainer-domain-handling-bug-fix.html

Here is the solution:

- Don't use .Add(Cookie), Use only .Add(Uri, Cookie) method.

Call BugFix_CookieDomain each time you add a cookie to the container or before you use .GetCookie or before system use the container.

private void BugFix_CookieDomain(CookieContainer cookieContainer)
{
    System.Type _ContainerType = typeof(CookieContainer);
    Hashtable table = (Hashtable)_ContainerType.InvokeMember("m_domainTable",
                               System.Reflection.BindingFlags.NonPublic |
                               System.Reflection.BindingFlags.GetField |
                               System.Reflection.BindingFlags.Instance,
                               null,
                               cookieContainer,
                               new object[] { });
    ArrayList keys = new ArrayList(table.Keys);
    foreach (string keyObj in keys)
    {
        string key = (keyObj as string);
        if (key[0] == '.')
        {
            string newKey = key.Remove(0, 1);
            table[newKey] = table[keyObj];
        }
    }
}

Problem

I'm confused how CookieContainer handles domain, so I create this test. This test shows cookieContainer doesn't return any cookie for "example.com" but according to RFC it should return at least 2 cookies. Isn't it a bug? How make it to work? Here is a discussion about this bug: http://social.msdn.microsoft.com/Forums/en-US/ncl/thread/c4edc965-2dc2-4724-8f08-68815cf1dce6 ``` <%@ Page Language="C#" %> <%@ Import Namespace="System.Net" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> CookieContainer getContainer() { CookieContainer result = new CookieContainer(); Uri uri = new Uri("http://sub.example.com"); string cookieH = @"Test1=val; domain=sub.example.com; path=/"; result.SetCookies(uri, cookieH); cookieH = @"Test2=val; domain=.example.com; path=/"; result.SetCookies(uri, cookieH); cookieH = @"Test3=val; domain=example.com; path=/"; result.SetCookies(uri, cookieH); return result; } void Test() { CookieContainer cookie = getContainer(); lblResult.Text += "<br>Total cookies count: " + cookie.Count + " &nbsp;&nbsp; expected: 3"; Uri uri = new Uri("http://sub.example.com"); CookieCollection coll = cookie.GetCookies(uri); lblResult.Text += "<br>For " + uri + " Cookie count: " + coll.Count + " &nbsp;&nbsp; expected: 2"; uri = new Uri("http://other.example.com"); coll = cookie.GetCookies(uri); lblResult.Text += "<br>For " + uri + " Cookie count: " + coll.Count + " &nbsp;&nbsp; expected: 2"; uri = new Uri("http://example.com"); coll = cookie.GetCookies(uri); lblResult.Text += "<br>For " + uri + " Cookie count: " + coll.Count + " &nbsp;&nbsp; expected: 2"; } protected void Page_Load(object sender, EventArgs e) { Test(); } </script> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>CookieContainer Test Page</title> </head> <body> <form id="frmTest" runat="server"> <asp:Label ID="lblResult" EnableViewState="false" runat="server"></asp:Label> </form> </body> </html> ```

Original source