The cookie is still valid after 30 minutes, although I have set a longer expiration time

I useFormsAuthentication, use the followingCodeSetCookieThe expiration time of is set3Days

If (validateuser (txtusername. Text, txtpassword. Text ))
{
Httpcookie

authenticationcookie = formsauthentication. getauthcookie (txtusername. text, true);
authenticationcookie. expires = datetime. now. adddays (3); // 3 days
response. cookies. add (authenticationcookie);
response. redirect (formsauthentication. getredirecturl (txtusername. text, true);
}

But the actual running result is:CookieThe expiration time of is still30Minutes (this is where I amWeb. config), Instead3Days

.

Why? Please advise, thank you

[Answer:]

Web. configTo set a smooth expirationSlidingexpirationIsFalse

Http://msdn2.microsoft.com/zh-cn/library/system.web.security.formsauthentication.slidingexpiration (vs.80). aspx