what you can do is to set the cacheDependencyKey and then remove that once you want to invalidate the cache

Hi Quan

Thank you for your replay and time.

So the process should look something like this?

1. add the key with some empty value? 

   • CacheManager.Insert("cacheDependencyKey", new object());

2. call search with the key so the result is cached (and the change token is null then)

   • search.StaticallyCacheFor(TimeSpan.FromMinutes(10), null, "cacheDependencyKey")

3. remove the key when something happaned (creating a page event...)

   • CacheManager.Remove("cacheDependencyKey");

4. call search still with the key 

   • search.StaticallyCacheFor(TimeSpan.FromMinutes(10), null, "cacheDependencyKey")

and if I understand it correctly, the best time to add the key to cache would be just right after I get the search result, right?

Petr

No you should add they cache dependency before you get the search result. So you got it almost right already, just think it should be like this on cache invalidation

1. • CacheManager.Remove("cacheDependencyKey");
     CacheManager.Add("cacheDependencyKey", new object());

Also if you want to nuke all the Find search result cache, you can remove CacheUtils.MasterKey 

oh, now I get it! (and test it)  This really invalidated the cache:

CacheManager.Remove("cacheDependencyKey");
CacheManager.Add("cacheDependencyKey", new object());

search.StaticallyCacheFor(TimeSpan.FromMinutes(10), null, "cacheDependencyKey")

 Another question (which I can probable test) is if I set an expiration of that cachekey to let's say 5 minutes

new CacheEvictionPolicy(new TimeSpan(0, 5, 0), CacheTimeoutType.Absolute);

but the StaticallyCacheFor(TimeSpan.FromMinutes(10) is 10 minutes cache. I guess the cache will expire after 5 minutes, correct. The lowest time will just expire the cache here.

Thank you Quan!

IN theory, yes. the dependency key will expire after 5 minutes and the dependent caches will be removed too. My memory is a bit rusty but I think the general approach is to have the cache key object to live indefinitely (just like you add with just CacheManager.Add("cacheDependencyKey", new object()); ), so you only need to care about your StaticallyCacheFor time out.