GeekZilla
Stopping simultaneous logins (Forms Authentication)
The following code (called from a page load) will bump off users who are logged in when someone else logs in with the same credentials.
public bool ValidSession() { lock (Cache) { string requestUserSessionGUID; if (Session["requestGuid"] == null) { // User hasn't been seen yet.. we'll let this user take over control and bump the other user off requestUserSessionGUID = User.Identity.Name + Guid.NewGuid().ToString(); Session["requestGuid"] = requestUserSessionGUID; Cache.Insert("UserSessionID", requestUserSessionGUID); return true; } else { // This user has been here before, check the guid matches the one in the cache requestUserSessionGUID = (string)Session["requestGuid"]; // may be first hit if ((string)Cache["UserSessionID"] == null) { Cache.Insert("UserSessionID", requestUserSessionGUID); } string cachedUserSessionID = (string)Cache["UserSessionID"]; if (cachedUserSessionID == requestUserSessionGUID) { // we have a match, success return true; } else { // different, force logout FormsAuthentication.SignOut(); Session.Abandon(); return false; } } } }
Author Paul Hayman
Paul is the COO of kwiboo ltd and has more than 20 years IT consultancy experience. He has consulted for a number of blue chip companies and has been exposed to the folowing sectors: Utilities, Telecommunications, Insurance, Media, Investment Banking, Leisure, Legal, CRM, Pharmaceuticals, Interactive Gaming, Mobile Communications, Online Services.
Paul is the COO and co-founder of kwiboo (http://www.kwiboo.com/) and is also the creator of GeekZilla.
