list active sessionids

Question

Hi, how to get list of all active ASP.NET Sessionsid

Naimish Makwana · Answer

To get a list of all active ASP.NET Session IDs, you can use a combination of code in your Global.asax file and some reflection. Here’s a basic example: Track Sessions in Global.asax : Add session IDs to a list when a session starts. Remove session IDs from the list when a session ends. public class Global : System.Web.HttpApplication { private static readonly List _sessions = new List (); private static readonly object padlock = new object(); public static List Sessions { get { return _sessions; } } protected void Session_Start(object sender, EventArgs e) { lock (padlock) { _sessions.Add(Session.SessionID); } } protected void Session_End(object sender, EventArgs e) { lock (padlock) { _sessions.Remove(Session.SessionID); } } } Retrieve Active Sessions : Use reflection to access the internal session state. public static IEnumerable GetActiveSessions() { var sessions = new List (); var obj = typeof(HttpRuntime).GetProperty("CacheInternal", BindingFlags.NonPublic | BindingFlags.Static).GetValue(null, null); var obj2 = (object[])obj.GetType().GetField("_caches", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(obj); foreach (var cache in obj2) { var c2 = (Hashtable)cache.GetType().GetField("_entries", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(cache); foreach (DictionaryEntry entry in c2) { var o1 = entry.Value.GetType().GetProperty("Value", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(entry.Value, null); if (o1.GetType().ToString() == "System.Web.SessionState.InProcSessionState") { var sessionId = (string)o1.GetType().GetField("_sessionId", BindingFlags.NonPublic | BindingFlags.Instance).GetValue(o1); sessions.Add(sessionId); } } } return sessions; } This approach works for InProc session state mode. If you’re using StateServer or SQLServer modes, you’ll need a different approach as Session_End won’t be triggered12. Thanks