public void CleanupInitializedFiles(DateTime cleanupThreshold) { var filesToFinalize = new List<string>(); // Select the files require to be finalized. foreach (var file in this.initializedFiles) { if (file.Value < cleanupThreshold) { filesToFinalize.Add(file.Key); } } // Finalize the files. foreach (string fileName in filesToFinalize) { this.FinalizeFile(fileName); } }