Ok it's not necessarily true in all cases but....
I am
currently putting the finishing touches to a business directory I have
built using ASP.NET 2.0. I have used a lot of the .NET 2.0 web
controls for the project, and at the beginning all was well. But as
the application grew and I needed to use more SQLDataSources, Repeaters
and DropDownList boxes, I noticed that the pages seemed to lag for
maybe a couple of seconds before loading.
I (Foolishly)
decided to use an Access Database when starting this app, so instantly
thought it must be my good old AccessDB playing up. So I went through
the app and upgraded it so that everything ran off a nice SQL DB. -
Still there was some lag on start up which was getting on my
nerves...
After a bit of investigation and reading through my copy of Stephen Walthers - ASP.NET 2.0 Unleashed (Which I have found to be a fantastic book)
I started reading more about ViewState. Upon this newly found
information I opened up my default page (Which was the main culprit for
hanging) and found this:
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPD
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dgs=" />
Now
the thing is this page has absolutely no need to use ViewState, so I
was a touch confused why I had the above... Anyhow... In the unleashed
book it explains how to disable ViewState via the page directive using
the EnableViewState="false"
<%@ Page Language="VB" EnableViewState="false" %>
NOTE: If you want to turn off viewstate for you entire website and not just one page you can also do it in your web.config file
<system.web>
<pages enableViewState="false" />
</system.web>
I
then relaunced the page and the slight lag I had disapeared!! Thus a
valuable lesson learnt in the ASP.NET world. If your hot on your app's
speed then check if you actually need viewstate enabled on a particular
page - If not turn it off.. Its easy enough to turn back on!