Random Page_Load calls on back button in ASP.NET

Question

Hey all,

I'm hoping someone has seen this before because I can't for the life of me find the problem.

I'm trying to do the old "fix the back button" thing in an application and I think i have a pretty decent approach, the problem is that it relies on the application not calling page_load when you hit back and instead loading the cached version of the page.

On about 60% of my pages that's exactly what happens. It loads the cached version and all is well. On the other 40% when i hit the back button page_load calls, forcing a refresh. For reference the call to page_load is NOT in a postback.

Even stranger is that this only occurs in IE (6 & 7). In firefox page_load never gets called.

I am using ASP.NET Ajax framework on both types of pages. Anyone seen anything like this before?

--Update--

After investigating a bit more I'm finding out that when i use the search to navigate from one page to another the application behaves differently for different pages. On the broken pages the page_load gets called twice, the search gets called twice and in fiddler that turns into 2 different redirect postbacks the second of which has no-cache set.

On the working page page_load and search only happen once and it immediately redirects.

That second Response.Redirect is causing the issue. Still not sure why that's happening though.

Answer 1

if you are using ASP.NET AJAX why not using the History server control object?

replacing History, the back button will go to the link you want.

try this

Answer 2

Check what the server is returning for the cache-control http header, then try setting Response.Cache.SetCacheability()/ use the output cache page directive on the pages and see if the server is saying that the pages should be cached.