ASP.NET Tips #2 - Avoid using session state

Where possible, you should try and avoid using session state. Whilst using one web server, performance is usually not a problem. This changes as soon as you need to scale to multiple servers, as different, and usually slower, techniques need to be used.

Session State in ASP.NET can be enabled and disabled both at the page and application levels. This section discusses how we can enable and disable Session state at both the page and application levels.

Page Level

We can disable Session State for the pages that do not require access to Session data using the EnableSessionState statement in the Page directive of a page as shown below:

   <%@ Page EnableSessionState="False" %>

Session State for a page can also be set to read only for pages that require access to the Session data, but do not modify them. Refer to the statement below:

   <%@ Page EnableSessionState="ReadOnly" %>

Application Level

Session State can also be disabled for all the pages of the application by specifying the same at the application level in the configurations section of the web.config file.

<configuration>
  <system.web>
    <pages enableSessionState="False" />
  </system.web>
</configuration>

It is also possible to set the Session State to read-only for all the pages in the application.

<configuration>
  <system.web>
    <pages enableSessionState="ReadOnly" />
  </system.web>
</configuration>