public void Update()
{
List <string> delList = new List <string>();
foreach (KeyValuePair <string, List <ResourceCacheItem> > kv in cacheDict)
{
for (int i = kv.Value.Count; i >= 0; i--)
{
ResourceCacheItem item = kv.Value[i];
item.retainTime--;
if (item.retainTime <= 0)
{
kv.Value.RemoveAt(i);
loader.DeleteResource(kv.Key);
if (kv.Value.Count == 0)
{
delList.Add(kv.Key);
}
}
}
}
for (int i = 0; i < delList.Count; i++)
{
cacheDict.Remove(delList[i]);
}
}