Can I clear browser cache of the page leaving page? - html

Can I clear browser cache of the page when I'm leaving it.
// Clear browser cache
Response.Redirect("otherpage.html");
By "clean browser cache" I didn't mean all the cache. I meant make user download the page next time he goes back to it (by pressing back button in my case).
Edit
Usually Sky Sanders suggestion works. In fact that what I tried right away, but even though it worked for simple page it failed when putting Response.Redirect after cache headers. Even though FF received headers it still provided me with a cached page when I pressed back button.

The only way you can control caching from the content end of the stick is to prevent caching in the first place.
context.Response.Cache.SetExpires(DateTime.UtcNow.AddMinutes(-1));
context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
context.Response.Cache.SetNoStore();
You cannot invoke methods on the client browser.

No, you can't clear the browser cache from your web app. You could clear the cookies but that's about it.

Related

Chrome caching page when pressing previous button

i have a page that displays a list with vuejs, the user can do some update on this list (filters). Whenever he go to another page and then click the back button on the browser, there are still the old parameters (filters), he needs tu press refresh to get it right.
These information are sent from the PHP controller, and are corrects.
Is there a way to prevent browser caching ? i found other topics on the same problem, but no answer was really fine (mostly force page reload, which is not really fine for UX)
do you know any better solution ?
Try deleting the cookies and local storage objects, should work see here:
Clearing localStorage in javascript?

Single Page Application: Disable fast back from Browser?

I have single page application(Rails if it matters), where I am struggling with Browser cache. When user press back button It loads page from cache, not even HTTP 304. I have already set no-cache in response, but I belive browser has another layer of cache on top for single page application to provide fast back.
I understand there are some solutions here:-
Disable browser back button for one page application
https://softwareengineering.stackexchange.com/questions/256363/dealing-with-browser-cache-in-single-page-apps
However all of them involve, having either a popup box, or disabling back button. Both I think are terrible UX choices. Is there any other way to force browser to query server in SPA?

'Back' button and 'history.go(-1)' not working with Chrome

Got an odd problem, only persistent in Chrome browser. Can't imagine what would be the problem. Chrome's "Back" button doesn't work, nor does history.go(-1), but works fine on all other browsers. To see the problem simply click this link, which will asynchronously initiate searches on two separate services, or sites if you will. Upon click on any search result list item, we traverse to another page, but "Back" doesn't work for Chrome.
http://vps-net.com/MSSMine/?search=some
Any suggestions or ideas are welcome.
I found the problem with the page you have linked, I don't believe it to be an issue with Chrome.
When you load the page, it also loads two iFrames as the request to the site finishes. Chrome takes a somewhat different approach to history, allowing you to navigate not simply from changes in the URL displayed, but through every new individual browser-initiated request. When the iFrames load, Chrome adds history for each step of the page loading process, creating 4 separate history items. When you go back 1 "page load", it takes you back to the site you linked to, at a different step in the process. You aren't seeing anything change because as soon as that page loads, any unloaded iFrame now loads again.
If you do history.go(-8) or some other large number, you should see the page at that many pageloads ago. However, if the link is opened "in a new tab" then the history begins for that tab at the URL you told it to open, effectively limiting the history to the pages that occurred during that tab's lifespan.
This was tested on Chrome 34.0.1847.116 running under Ubuntu 13.10.
My back button was not working as well, but it would not work with any browser. I went into my add/delete software and deleted what software was added the night before - BOOM! All is fine now.

Is swapCache() required in HTML5 offline apps?

If I don't implement any updateready event handler and don't call swapCache(), does that mean that the browser will always use the first (oldest) downloaded version of the application?
If no, then why is the swapCache() method needed?
Swapcache makes sure that "subsequent" calls to cached resources are taken from the new cache.
Subsequent meaning after swapcache.
To see this in action try setting the src property of an img dynamically after the
swapcache call in the updateready event (so that the browser loads it at that particular
time). Make sure this image is not already loaded elsewhere in the page since that will
distort this test.
Now change the image and change the manifest files (to force reloading the cached files).
Reload the page in your browser.
You should now see the new version of the image in your rendered page.
Now comment out the call to swapcache.
Make a change to the manifest file and reload the page and thus all resources.
Refresh the page again (to make sure you have a version from the new cache).
Now change the image again and change the manifest.
Again reload the page: now you see the old version of the image.
In the last case, the browser finished loading the new versions in cache, but since
swapcache was not called, the image was still taken from the old cache.
If you do not do any dynamic loading of resources in your page, the swapcache has no effect.
In particular, if you reload the page in the updateready event handler calling swapcache
first has no effect since reloading the page will get it from the new cache anyway.
I have an app with a pretty large cache (>100mb). This takes a particularly long time to swap the cache in (and pretty much locks the browser while this is happening). So I display a message indicating that the app is updating (please wait...), then call swapCache(), then display a new message when it's done indicating completion.
Not sure if this answers your question (as to why it's necessarily needed), but I think it provides a valid use case for swapCache() at least.
Let's imagine 2 different scenarios.
You call location.reload() when the new content is available. The page will reload using its all-new content. applicationCache.swapCache() is not needed in this case.
Your user continues to interact with your page, without any reload. This interaction causes an asset to load dynamically. For the sake of argument, let's imagine that it's a rollover image, and let's imagine that you have just updated this rollover image. Without applicationCache.swapCache(), your user will continue to see the old rollover image. After applicationCache.swapCache(), s/he will see the new rollover image.
So applicationCache.swapCache() without a reload says: "Keep the page looking the way it was when it was loaded, but use any new assets now, as soon as the page asks for them".
The SwapCache method provides a mechanism for the application to be in control of how an when updates are applied. In regular HTML apps, it can be difficult to determine if the correct JS is present on the clients browser.
Also browser implementations vary on when a cache would be updated, I found the iPhone particularly stubborn. swapCache put me back in control of how my app is updated i.e. I could choose to automatically apply the patch or let the user choose when to apply etc.
I was wondering the same thing. I seem to be able to trigger a successful update by just calling "window.applicationCache.update()". If the manifest file has been modified, the 'download' event is triggered, then eventually the "update ready".
When I reload it, it appears to have been applied. I don't seem to need to call swapCache(). I have provision for calling it from the app, but so far have not noticed any effect on the update process.
Calling update() basically eliminates one reload, AFAICS.
swapCache will switch from the previous set of resources listed in the cache manifest (when the running webapp was loaded) to the new set. You are doing this in response to an updateready after all, which signals that a new manifest has been loaded.
This is not to be confused with loading individual resources, for which the usual browser caching policies still apply. In other words you will swap set of resources, but individual resources need their own cache management to ensure they're reloaded when you need them to.
I haven't tried this yet, but it would seem to suggest structuring the code as an "update controller" javascript file that handles the update process, and javascript sources with a versioned filename (or URL) with known entry points.

What would cause a visitor to return to the top of the previous page, instead of to the point in the page where the link resides?

I've seen this weird behavior on several sites recently: I scroll down a page and follow a link to another page. When I click the Back button and return, I am left back at the top of the previous page, not at the link. This is very annoying if I'm clicking on links in a search results page or a list of "10 Best Foo Bars...".
See this page as an example. Strangely, the page works as expected in IE6 on WinXP, but not on FF2 on the same machine. On Mac OS X 10.4 it works in FF2, but not in FF3. I checked for any weird preference settings, but I can't find any that are different.
Any idea what is causing this?
Many sites have a text box (for searching the site, or something) that is set to automatically take focus when the page loads (using javascript or something). In many browsers, the page will jump to that text box when it gets focus.
It really is very annoying :(
Typically this behaviour is caused by the browser cache set by the site having a small or no time before expiry.
On many sites, when you hit "back" you get brought back to the link you hit, as your browser is pulling the page from your cache. If this cache has not been set, a new page request is made, and the browser treats it as fresh content.
On the page linked above, the "Expires" header seems to be set to less than a minute ahead of my local clock, which is causing my browser to get a fresh copy when I hit "back" after that expiry time.