I have ASP.NET pages that I want cached on BOTH the client and server
sides. I am currently setting the cache policy through code rather
than OutputCache directive:

HttpContext.Current.Response.Cache.SetValidUntilEx pires(true);
HttpContext.Current.Response.Cache.SetCacheability (HttpCacheability.Public);
HttpContext.Current.Response.Cache.SetExpires(Date Time.Now.AddMinutes(10);

This seems to work fine as the pages are being cached on the client.
My question is does the page actually get cached on the client AND
server side. I.e. After a page is expired on the client and a request
is made to the server, is a server-side cached version of the page
returned? Or is the page re-executed on the server for every single
client whose copy has expired?

Thanks in advance!

Neal

The page will not be cached server-side unless you use the outputcache
feature. The code you listed is only caching client-side.

--
Ben Strackany
www.developmentnow.com

<a href="http://www.developmentnow.com">dn</a>


<nkranes (AT) gmail (DOT) com> wrote

nkranes (AT) gmail (DOT) com wrote:
In additon to Ben's reply, let me add you're confusing HTTP caching with
application server specific caching. Your code makes your content cacheable
on web clients and proxies, but has nothing to do with ASP.NET owns caching
facilities.

BTW, you should also call

TimeSpan ts = new TimeSpan(0, 10, 0);
HttpContext.Current.Response.Cache.SetMaxAge(ts);

for full HTTP 1.1 compliance.

Cheers,

--
Joerg Jooss
www.joergjooss.de
news (AT) joergjooss (DOT) de

So what you're saying is that to enable Client-side (HTTP) and Server
side (Application) caching I need to include the above code plus the
outputcache directive? According to the documentation, I thought
Response.Cache and the OutputCache were used interchangably?

in the request stream either declaratively or programmatically as well.
In the @ OutputCache directive for a page you can use the Location
attribute to specify whether the page's output can be cached on proxy
servers, browser clients, the originating Web server, or all or none of
these. You can do the same programmatically using the
HttpCachePolicy.SetCacheability method to specify the appropriate
HttpCacheability enumeration value for your page.

Thoughts?

nkranes (AT) gmail (DOT) com wrote:
No...

Yes, you can. Actually, I should have written "HttpCachePolicy mixes up HTTP
caching and application server specific caching".

There's no notion of caching content on the origin server in HTTP, thus
setting HTTP headers using @OutputCache or HttpCachePolicy only affects
downstream proxies or clients.

If you want to have your cake and eat it, use
<%@ OutputCache Duration="600" VaryByParam="None" Location="Any" %>

This will allow caching everywhere. Even if a client request gets back to
the origin ASP.NET server, it simply replies with the cached response but
counts down the "Cache-Control: max-age" header -- very nice!

Cheers,

--
Joerg Jooss
www.joergjooss.de
news (AT) joergjooss (DOT) de

I hate to say it but you are correct. The only way to cache on the
Server and Client seems to be using the OutputCache directive. I still
think the documentation for the caching API is a bit misleading in this
regard and that there should be a way to programmatically do this.
Thanks for your help!

My bad, I was reading it wrong. I should have said that your code is caching
client side & server side.

Response.Cache.SetExpires & Response.Cache.SetCacheability

are interchangeable with the @outputcache parameter

which AFAIK will invoke server-side & client-side caching per the location
parameter.

http://msdn.microsoft.com/library/de...utputCache.asp

--
Ben Strackany
www.developmentnow.com

<a href="http://www.developmentnow.com">dn</a>


"Ben Strackany" <infoNOSPAM (AT) developmentnow (DOT) nospam.com> wrote

The documentation seems to imply that they're interchangeable, but maybe
not.

--
Ben Strackany
www.developmentnow.com

<a href="http://www.developmentnow.com">dn</a>


<nkranes (AT) gmail (DOT) com> wrote

nkranes (AT) gmail (DOT) com wrote:
Actually, I didn't want to imply that the "Any" option is only available
through OutputCache directive. It was only your reply that made me check
again. And yes, there seems to be no direct equivalent of Location="Any"
when using the API, but I'm sure you can construct it using several
HttpCachePolicy calls.

Cheers,

--
Joerg Jooss
www.joergjooss.de
news (AT) joergjooss (DOT) de