/// <summary>
/// Removes one item from cache when the cache hits the maximum size and a new item is to be put inside.
/// </summary>
private static void CleanUp()
{
RemoveDirtyItems(); // remove dirty and re-check if still cache is full
if (cache.Count >= Globals.ThisAddIn.Application.Worksheets.Count + CACHE_BUFFER_SIZE)
{
// If cache size exceeded the limit, remove one item keeping the recent items.
CachedSequenceData itemToRemove = null;
string keyToRemove = string.Empty;
foreach (var item in cache)
{
if (itemToRemove == null)
{
itemToRemove = item.Value;
keyToRemove = item.Key;
}
if (itemToRemove.LastAccessTime > item.Value.LastAccessTime)
{
itemToRemove = item.Value;
keyToRemove = item.Key;
}
}
cache.Remove(keyToRemove);
}
}
/// <summary>
/// Add a new item to the cache
/// </summary>
/// <param name="range">Range to use as the key for caching</param>
/// <param name="dataToCache">Object to be cached</param>
/// <param name="inputParamsAsKey">Input param names as key</param>
/// <returns>True if caching was successful</returns>
public static bool Add(IEnumerable <Range> selectedRanges, object dataToCache, string inputParamsAsKey)
{
CleanUp(); // cleanup as cache may be full or this sheet may be marked dirty already
string key = GetRangeAddress(selectedRanges, inputParamsAsKey);
if (cache.ContainsKey(key)) // remove if exists
{
cache[key] = new CachedSequenceData(dataToCache);
}
else
{
cache.Add(key, new CachedSequenceData(dataToCache));
}
return(true);
}
/// <summary>
/// Trys to get a sequence from the cache for the given range list
/// </summary>
/// <param name="range">Range list for which the request is made</param>
/// <returns>Returns the sequence object or null if not found</returns>
public static object TryGetSequence(IEnumerable <Range> selectedRanges, string inputParamsAsKey)
{
RemoveDirtyItems();
string key = GetRangeAddress(selectedRanges, inputParamsAsKey);
if (cache.ContainsKey(key))
{
CachedSequenceData seq = cache[key];
seq.LastAccessTime = DateTime.Now;
return(seq.CachedData);
}
else
{
return(null);
}
}
