More on Syncronized - upgrade reader to writer
In using my new sync wrapper to clean up a bunch of older code, I came across the need to be able to upgrade from a reader to a writer for certain operations. One example of this it to clean up expired items in my my implementation of a Cache.
protected Synchronized<Dictionary<string, ICacheItem>> _syncDictionary =
new Synchronized<Dictionary<string, ICacheItem>>(new Dictionary<string, ICacheItem>());
...
private void PurgeExpired() {
_syncDictionary.ReadUpgradeableToWrite((dictionary, reader) => {
List<ICacheItem> expired = new List<ICacheItem>();
foreach (ICacheItem cacheItem in dictionary.Values) {
if (cacheItem.IsExpired) {
expired.Add(cacheItem);
}
}
if (expired.Count > 0) {
reader.UpgradeToWriter();
foreach (ICacheItem cacheItem in expired) {
ItemRemovedInternal(cacheItem);
dictionary.Remove(cacheItem.CacheKey);
}
}
return true;
});
}
I cleaned up the code a bit, and am making it available here. Free to use, no waranty on fitness.