force users to logout

Currently I have a client and admin webpage. There are multiple users who will login to the client page. While in admin page, when I restored the database inside the admin page, I need to logout all the users who are currently login to the client page开发者_运维知识库. Any ideas how it should be done? My current language using is classic ASP. If it can be done in ASP.NET, its fine too. Thanks.

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It really depends what you've cached. If it's data then you can clear the cached data rather than forcing your users to login again.

If it's data or permissions / security change then you could have a setting in your database called SchemaVersion that stores the current version of the database. Each logged in user request to the app could compare the cookie / session version against the one in the database and if it differs to get the client to delete the session / cookie and force a re-login.

According to a Microsoft help article you can reset the session like this:

Session.Abandon(); 
Response.Cookies.Add(new HttpCookie("ASP.NET_SessionId", ""));

And from MSDN you can clear your cookie like this:

if (HttpContext.Current.Request.Cookies["MyCookieName"] != null)
{
    HttpCookie aCookie = HttpContext.Current.Request.Cookies["MyCookieName"];
    aCookie.Expires = DateTime.Now.AddDays(-10);
    aCookie.Value = "";
    HttpContext.Current.Response.Cookies.Add(aCookie);
}

This should force a login, but I haven't confirmed this myself.

So in summary, you can use the ASP.NET Cache to store the db schema version and:

At the start of the page load call a helper class LoginResetHelper.IsDbValid() to see if we need to login again

In the helper class you would ask

if (Cache["SchemaVersion"] == null)
{
   // retrieve schemaVersion from db

   Cache.Add("SchemaVersion", schemaVersion);
}
HttpCookie oCookie = new HttpCookie("ClientSchemaVersion");
if (Cache["SchemaVersion"] == oCookie.Value)
   return true;
return false;

If IsDbValue is true, the continue as normal

If it is false, then call the LoginResetHelper.ResetLogin() and redirect to login page.

In ResetLogin() you would perform the clearing functions I mentioned above

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Maybe easiest way is to define an Application variable indicating your website in under maintenance and, in every page through a server side include, check that variable and redirect to an appropriate error page.