Dicom.Data.DcmDataset.GetElement C# (CSharp) Method

        public DcmElement GetElement(DicomTag tag)
        {
            DcmItem item = null;
            if (!_items.TryGetValue(tag, out item))
                return null;
            if (item is DcmElement)
                return item as DcmElement;
            return null;
        }

        private static Expression<Func<Study, bool>> FilterByModality(DcmDataset query)
        {
            Expression<Func<Study, bool>> allMatch = p => true;

            var studyQuery = query.GetElement(DicomTags.ModalitiesInStudy);

            if (studyQuery == null)
                return allMatch;

            var valueString = studyQuery.GetValueString();

            if (String.IsNullOrWhiteSpace(valueString))
                return allMatch;

            var modalities = valueString.Replace(@"\\", @"\").Split('\\');

            if (modalities.Length == 1)
            {
                return s => s.ModalityAggregation.Contains(modalities[0]);
            }
            else
            {
                return s => s.Series.Any( series => modalities.Contains(series.PerformedModalityType));
            }
        }