Public Function IndexOf( _
   ByVal Object As DicomDataSet _
) As Long

The value returned locates the first occurrence of the specified object within the collection.  In the case of DicomImages, DicomDataSets or DicomLabels collections, the reference may be to an object derived from the same source, as such objects may be cloned when added to collections.

DicomDataSets Collection  | DicomDataSets Members