session object

[prasad.unvss]

how can i instantialize the system.web.sessionstate.httpsessionstate
class and one more doubt can a class can be defined without
constructors

 

[Alberto Poblacion]

how can i instantialize the system.web.sessionstate.httpsessionstate
class

You don't. Asp.Net wil do that for you. You access the (already
instantiated) HttpSessionState through the Session property of the Page
class, or by means of a call to HttpContext.Current.Session.

and one more doubt can a class can be defined without
constructors

You can write a class without any constructor in your source code, but in
that case the compiler will automatically create a default (empty)
constructor.
If you want a class that cannot be constructed, you can define a private
constructor. This will prevent the class from being instantiated (unless you
provide a static method inside the class which creates an instance). A class
that cannot be instantiated can be useful for containing static methods.