+ * \brief Get the first entry while visiting *the* 'zero level' DocEntrySet
+ * (DocEntries out of any Sequence)
+ * \return The first DocEntry if found, otherwhise NULL
+ */
+DocEntry *ElementSet::GetFirstEntry()
+{
+ ItTagHT = TagHT.begin();
+ if (ItTagHT != TagHT.end())
+ return ItTagHT->second;
+ return NULL;
+}
+
+/**
+ * \brief Get the next entry while visiting *the* 'zero level' DocEntrySet
+ * (DocEntries out of any Sequence)
+ * \note : meaningfull only if GetFirstEntry already called
+ * \return The next DocEntry if found, otherwhise NULL
+ */
+DocEntry *ElementSet::GetNextEntry()
+{
+ gdcmAssertMacro (ItTagHT != TagHT.end());
+
+ ++ItTagHT;
+ if (ItTagHT != TagHT.end())
+ return ItTagHT->second;
+ return NULL;
+}
+
+/**
+ * \brief retrieves a Dicom Element using (group, element)
+ * @param group Group number of the searched Dicom Element
+ * @param elem Element number of the searched Dicom Element
+ * @return
+ */
+DocEntry *ElementSet::GetDocEntry(uint16_t group, uint16_t elem)
+{
+ TagKey key = DictEntry::TranslateToKey(group, elem);
+ TagDocEntryHT::iterator it = TagHT.find(key);
+
+ if ( it!=TagHT.end() )
+ return it->second;
+ return NULL;
+}
+
+/**
+ * \brief Copies all the attributes from an other DocEntrySet
+ * @param set entry to copy from
+ * @remarks The contained DocEntries a not copied, only referenced