How do I check the "createPersistentCookie" in ASP.NET Forms Authentication?

When someone logs into my application and they checked the "Remember Me" checkbox, I set the createPersistentCookie = true so that wh开发者_运维百科en they come back they don't need to log in again. However, occassionally, I need to use the FormsAuthentication.SetAuthCookie(NewUserName, [true/false]) so how do I know if they originally set the createPersistentCookie to true or not so I can keep it the same as it was when they logged in?

I believe when you decrypt the cookie you should be left with a FormsAuthenticationTicket which you can then query the IsPersistent property.

To decrypt:

FormsAuthenticationTicket ticket = FormsAuthentication.Decrypt(Request.Cookies[FormsAuthentication.FormsCookieName].Value);

References: FormsAuthentication.Decrypt() on MSDN

You should also remember to set in your application's web.config to constant value. ASP.NET has tendency to auto generate this values after some time.

For more info please take look at: http://msdn.microsoft.com/en-us/library/w8h3skw9(v=VS.90).aspx