WebService.Application Property

XML Web services can use both application state and session state. Application state is maintained across all sessions accessing an XML Web service regardless of whether session state is turned off for a method(by using the EnableSession property of the WebMethodAttribute).

The example below demonstrates a hit counter, incrementing the count every time a browser calls the XML Web service method.

<%@ WebService Language="C#" Class="Util"%>
 using System.Web.Services;

 public class Util: WebService {
   [ WebMethod(Description="Application Hit Counter",EnableSession=false)]
    public int HitCounter() {
       if (Application["HitCounter"] == null) {
          Application["HitCounter"] = 1;
       }
       else {
          Application["HitCounter"] = ((int) Application["HitCounter"]) + 1;
          }
       return ((int) Application["HitCounter"]);
    }   
 }
    

.NET Framework

.NET Framework Client Profile

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference