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Managing State in XML Web Services Created Using ASP.NET
XML Web services have access to the same state management options as other
ASP.NET applications when the class implementing the XML Web service derives
from the WebService class. The WebService class contains many of the common
ASP.NET objects, including the Session and Application objects.
The Application object provides a mechanism for storing data that is
accessible to all code running within the Web application, whereas the
Session object allows data to be stored on a per-client session basis. If
the client supports cookies, a cookie can identify the client session. Data
stored in the Session object is available only when the EnableSession
property of the WebMethod attribute is set to true for a class deriving from
WebService. A class deriving from WebService automatically has access to the
Application object.
