Taken from https://github.com/secretGeek/til/blob/master/asp.net_mvc/from_memory.md

Handy Cache helper method

I love this little thing.

public static T FromMemory<T>(string Key, Func<T> func, double days = 7) where T : class
{
    var value = MemoryCache.Default.Get(Key) as T;
    if (value == null)
    {
        value = func();
        if (value != null)
        {
            MemoryCache.Default.Add(Key, value, DateTime.Now.AddDays(days));
        }
    }

    return value;
}

Then, instead of simply retrieving something from storage, e.g.

var items = LoadSiteMap();

You do this slightly awkward, but fairly clean alternative:

var items = Latest.FromMemory("SiteMap", () => LoadSiteMap());

You do have to tell it the cache_key to use.

You can override the default duration to hold it in memory...

var items = Latest.FromMemory("SiteMap", () => LoadSiteMap(), 0.1);

And if things go really pear shaped, and it can't infer the types, you might need to specify them, for example here:

var items = Latest.FromMemory<List<ISitemapItem>>("SiteMap", () => LoadSiteMap(), 0.1);

Jogai/from_memory.md

Handy Cache helper method