How to clear Sitecore item from cache

Question

I believe Sitecore is caching an item's workflow value and I need to be able to clear it.

The scenario is that I issue an ajax request to determine whether a specific item exists and if it does exist retrieve its Workflow field value. The user fills out a form and they have the options to Save or Submit that form; when they submit the form it enters a Workflow state. However, even if I switch browsers the LoiHasNoWorkflow keeps the previous value unless I publish again. I have a method to clear some caches but I'm not sure which might be actually caching the field.

    public static bool ClearCache()
    {
        foreach (DictionaryEntry entry in HttpContext.Current.Cache)
        {
            HttpContext.Current.Cache.Remove((string)entry.Key);
        }

        Context.Database.Engines.TemplateEngine.Reset();
        Context.ClientData.RemoveAll();
        CacheManager.ClearAllCaches();

        return true;
    }

public bool LoiHasNoWorkflow => CBUtility.ClearCache() && string.IsNullOrEmpty(loi?.Fields["__Workflow"].Value);

How can I determine why the item's __Workflow value won't clear? I can even delete the item through Sitecore UI, refresh the page, and issue the same request but get the value when the item did exist.

Are your ajax request and form submit accessing the master database? When you read LoiHasNoWorkflow it is accessing the web database? — Ben Golden

uioporqwerty uioporqwerty · Accepted Answer · 2016-05-07T02:04:45

Actually the issue turned out to be not related to the cache but my own mistake. My loi object was a static variable within that class and so it wasn't getting cleared out on every page refresh. Here is the SO deeper explanation that led me to this realization. Actually learned a bit more about how static variables.

Lifetime of ASP.NET Static Variable

How to clear Sitecore item from cache

1 Answers