Chapter 8 part2

• Session State Configuration
• Session Modes in ASP.NET
 InProc
 StateServer
 SQLServer
 Custom
• Application State
• An Overview of State Management Choices

You configure session state through the web.config file.
The configuration file allows you to set advanced options
such as the timeout and the session state mode.

<sessionState
cookieless="UseCookies"
cookieName="ASP.NET_SessionId"
regenerateExpiredSessionId="false"
timeout="20"
mode="InProc"
stateConnectionString="tcpip=127.0.0.1:42424"
stateNetworkTimeout="10"
sqlConnectionString="data source=127.0.0.1;Integrated Security=SSPI"
sqlCommandTimeout="30"
allowCustomSqlDatabase="false"
customProvider=""
compressionEnabled="false"/>

You can set the cookieless setting to one of the values
defined by the HttpCookieMode enumeration,

This specifies the number of minutes that ASP.NET will
wait, without receiving a request, before it abandons the
session.

You can also programmatically change the session
timeout in code. For example, if you know a
session contains an unusually large amount of
information, you may need to limit the amount of time
the session can be stored.

Session.Timeout = 10;

In ASP.NET, there are the following session modes
available:

InProc : It instructs session state information to be
stored in the application domain
StateServer : With this setting, ASP.NET will use a
separate Windows service called StateServer for state
management.
SQLServer : This setting instructs ASP.NET to use an
SQL Server database to store session information
Custom : This setting use custom or third-party(e.g
Oracle) provider to store state information
Off : This setting disables session state management

InProc is the default mode. It instructs information to
be stored in the application’s domain, or in the main
ASP.NET process, which provides the best
performance but the least durability.

If you restart your server, the state information will be
lost.

In ASP.NET, application domains can be restarted for
a variety of reasons, including configuration changes
and updated pages, and when certain thresholds are
met.

With this setting, ASP.NET will use a separate
ASP.NET State Service for state management.

This service runs on the same web server, but it’s
outside the main ASP.NET process, which gives it a
basic level of protection if the ASP.NET process needs
to be restarted.

When using the StateServer setting, you need to
specify a value for the stateConnectionString.

This string identifies the TCP/IP address of the
computer that is running the StateServer service
and its port number.

For local server it is 127.0.0.1.

Use the Microsoft Management Console (MMC).

1. Select Start ➤ Control Panel.
2. Open the Administrative Tools group, and then choose
Computer Management.
3. In the Computer Management tool, go to the Services
and Applications ➤ Services node.
4. Find ASP.NET State Service in the list
5. You can manually start and stop the service by right-
clicking it. Select Properties, and modify the Startup
Type to Automatic to automatically start the service.

When using StateServer mode, you can also set an
optional stateNetworkTimeout attribute that specifies the
maximum number of seconds to wait for the service to
respond before canceling the request.

This setting instructs ASP.NET to use an SQL Server
database to store session information, as identified
by the sqlConnectionString attribute.

This is the most resilient state store but also the
slowest by far.

To use this method of state management, you’ll need
to have a server with SQL Server installed.

In addition, you need to install the special stored
procedures and temporary session databases.

These stored procedures take care of storing and
retrieving the session information.

ASP.NET includes a command-line tool called
aspnet_regsql.exe to install session storage
database on the current computer, and gives
default database name ASPState.

The easiest way to run aspnet_regsql.exe is to
open the Start menu and choose Programs ➤
Visual Studio 2010 ➤ Visual Studio Tools ➤ Visual
Studio Command Prompt.

The command that creates the session storage
database ASPState on the current computer is:

aspnet_regsql.exe -S localhost -E –ssadd

If you’re using a database named ASPState to store your
session information (which is the default), you don’t need to
supply the database name. Simply indicate the location of the
server and the type of authentication that ASP.NET should use
in the web.config file

<sessionState mode="SQLServer"
sqlConnectionString="data source=127.0.0.1;Integrated
Security=SSPI“ ... />

When using the SQLServer mode, you can also set an optional
sqlCommandTimeout attribute that specifies the maximum
number of seconds to wait for the database to respond before
canceling the request.

When using custom mode, you need to indicate which
session state store provider to use by supplying
the customProvider attribute which indicates the name of
the class.

The class may be part of your web application (in which
case the source code is placed in the App_Code
subfolder), or it can be in an assembly that your web
application is using (in which case the compiled
assembly is placed in the Bin subfolder)

Other vendors may release custom state providers you
want to use. For example, Oracle could provide a custom
state provider that allows you to store state information in
an Oracle database

The enableCompression setting only has an effect when
you’re using out-of-process session state storage.

When you set enableCompression to true, session data is
compressed before it’s passed out of the application domain.

There are two key scenarios where session state
compression makes sense:

• When the out-of-process state server is hogging a lot of memory
• When storing session state data on another computer

Application state allows you to store global objects that
can be accessed by any client.

The command to create Application variable:
Application["HitCounterForOrderPage"] = count;

// to retrieve an Application variable

int count = 0;
if (Application["HitCounterForOrderPage"] != null)
{
count = (int)Application["HitCounterForOrderPage"];
}

Application state isn’t often used, because it’s generally
inefficient.

Because two clients can access an application variable
at the same time, you need to use the Application.Lock()
and Application.Unlock() methods, which explicitly allow
only one client to access the Application state collection
at a time.

Application state is rarely used in the .NET world because its
two most common uses have been replaced by easier, more
efficient methods:

• In the past, application state was used to store application-
wide constants, such as a database connection string
which can be stored in the web.config file

• Application state can also be used to store frequently used
information that is time-consuming to create. It can be
replaced more efficiently with caching.

Chapter 8 part2

Recommended

More Related Content

What's hot (17)

Viewers also liked (9)

Similar to Chapter 8 part2 (20)

More from application developer (20)

Recently uploaded (20)

Chapter 8 part2