Software developer can use System.Web.SessionState.HttpSessionState member Count which returns the number of items in the current session collection. Related TutorialsHow to create a manual validation in ASP.NET 4.0 Behavioral properties of GridView control How to use XmlTextWriter formatting in VB.NET How to manage the ASP.NET web service output caching in VB.NET How to manage the ASP.NET web service session state in C#