System.Xml.Serialization.ClassMap.GetElement C# (CSharp) Method

		public XmlTypeMapElementInfo GetElement (int index)
		{
			if (_elements == null) return null;
			
			if (_elementsByIndex == null)
			{
				_elementsByIndex = new XmlTypeMapElementInfo [_elementMembers.Count];
				foreach (XmlTypeMapMemberElement mem in _elementMembers)
				{
					if (mem.ElementInfo.Count != 1) 
						throw new InvalidOperationException ("Read by order only possible for encoded/bare format");
						
					_elementsByIndex [mem.Index] = (XmlTypeMapElementInfo) mem.ElementInfo [0];
				}
			}
			
			return _elementsByIndex [index];
		}
		

		void ImportChoiceContent (XmlQualifiedName typeQName, ClassMap cmap, XmlSchemaChoice choice, CodeIdentifiers classIds, bool multiValue)
		{
			XmlTypeMapElementInfoList choices = new XmlTypeMapElementInfoList ();
			multiValue = ImportChoices (typeQName, null, choices, choice.Items) || multiValue;
			if (choices.Count == 0) return;

			if (choice.MaxOccurs > 1) multiValue = true;

			XmlTypeMapMemberElement member;
			if (multiValue)
			{
				member = new XmlTypeMapMemberFlatList ();
				member.Name = classIds.AddUnique ("Items", member);
				ListMap listMap = new ListMap ();
				listMap.ItemInfo = choices;
				((XmlTypeMapMemberFlatList)member).ListMap = listMap;
			}
			else
			{
				member = new XmlTypeMapMemberElement ();
				member.Name = classIds.AddUnique ("Item", member);
			}
			
			// If all choices have the same type, use that type for the member.
			// If not use System.Object.
			// If there are at least two choices with the same type, use a choice
			// identifier attribute

			TypeData typeData = null;
			bool twoEqual = false;
			bool allEqual = true;
			Hashtable types = new Hashtable ();

			for (int n = choices.Count - 1; n >= 0; n--)
			{
				XmlTypeMapElementInfo einfo = (XmlTypeMapElementInfo) choices [n];
				
				// In some complex schemas, we may end up with several options
				// with the same name. It is better to ignore the extra options
				// than to crash. It's the best we can do, and btw it works
				// better than in MS.NET.
				
				if (cmap.GetElement (einfo.ElementName, einfo.Namespace, einfo.ExplicitOrder) != null ||
					choices.IndexOfElement (einfo.ElementName, einfo.Namespace) != n)
				{
					choices.RemoveAt (n);
					continue;
				}
					
				if (types.ContainsKey (einfo.TypeData)) twoEqual = true;
				else types.Add (einfo.TypeData, einfo);

				TypeData choiceType = einfo.TypeData;
				if (choiceType.SchemaType == SchemaTypes.Class)
				{
					// When comparing class types, use the most generic class in the
					// inheritance hierarchy

					XmlTypeMapping choiceMap = GetTypeMapping (choiceType);
					BuildPendingMap (choiceMap);
					while (choiceMap.BaseMap != null) {
						choiceMap = choiceMap.BaseMap;
						BuildPendingMap (choiceMap);
						choiceType = choiceMap.TypeData;
					}
				}
				
				if (typeData == null) typeData = choiceType;
				else if (typeData != choiceType) allEqual = false;
			}

			if (!allEqual)
				typeData = TypeTranslator.GetTypeData (typeof(object));

			if (twoEqual)
			{
				// Create the choice member
				XmlTypeMapMemberElement choiceMember = new XmlTypeMapMemberElement ();
				choiceMember.Ignore = true;
				choiceMember.Name = classIds.AddUnique (member.Name + "ElementName", choiceMember);
				member.ChoiceMember = choiceMember.Name;

				// Create the choice enum
				XmlTypeMapping enumMap = CreateTypeMapping (new XmlQualifiedName (member.Name + "ChoiceType", typeQName.Namespace), SchemaTypes.Enum, null);
				enumMap.IncludeInSchema = false;

				CodeIdentifiers codeIdents = new CodeIdentifiers ();
				EnumMap.EnumMapMember[] members = new EnumMap.EnumMapMember [choices.Count];
				for (int n=0; n<choices.Count; n++)
				{
					XmlTypeMapElementInfo it =(XmlTypeMapElementInfo) choices[n];
					bool extraNs = (it.Namespace != null && it.Namespace != "" && it.Namespace != typeQName.Namespace);
					string xmlName = extraNs ? it.Namespace + ":" + it.ElementName : it.ElementName;
					string enumName = codeIdents.AddUnique (CodeIdentifier.MakeValid (it.ElementName), it);
					members [n] = new EnumMap.EnumMapMember (xmlName, enumName);
				}
				enumMap.ObjectMap = new EnumMap (members, false);

				choiceMember.TypeData = multiValue ? enumMap.TypeData.ListTypeData : enumMap.TypeData;
				choiceMember.ElementInfo.Add (CreateElementInfo (typeQName.Namespace, choiceMember, choiceMember.Name, choiceMember.TypeData, false, XmlSchemaForm.None, -1));
				cmap.AddMember (choiceMember);
			}
			
			if (typeData == null)
				return;
	
			if (multiValue)
				typeData = typeData.ListTypeData;

			member.ElementInfo = choices;
			member.Documentation = GetDocumentation (choice);
			member.TypeData = typeData;
			cmap.AddMember (member);
		}