System.Runtime.Serialization.Json.JsonFormatReaderGenerator.CriticalHelper.ReadGetOnlyCollection C# (CSharp) Method

            private void ReadGetOnlyCollection(CollectionDataContract collectionContract)
            {
                Type type = collectionContract.UnderlyingType;
                Type itemType = collectionContract.ItemType;
                bool isArray = (collectionContract.Kind == CollectionKind.Array);
                LocalBuilder size = _ilg.DeclareLocal(Globals.TypeOfInt, "arraySize");

                _objectLocal = _ilg.DeclareLocal(type, "objectDeserialized");
                _ilg.Load(_contextArg);
                _ilg.LoadMember(XmlFormatGeneratorStatics.GetCollectionMemberMethod);
                _ilg.ConvertValue(Globals.TypeOfObject, type);
                _ilg.Stloc(_objectLocal);

                bool canReadSimpleDictionary = collectionContract.Kind == CollectionKind.Dictionary ||
                                               collectionContract.Kind == CollectionKind.GenericDictionary;
                if (canReadSimpleDictionary)
                {
                    _ilg.Load(_contextArg);
                    _ilg.LoadMember(JsonFormatGeneratorStatics.UseSimpleDictionaryFormatReadProperty);
                    _ilg.If();

                    if (!type.GetTypeInfo().IsValueType)
                    {
                        _ilg.If(_objectLocal, Cmp.EqualTo, null);
                        _ilg.Call(null, XmlFormatGeneratorStatics.ThrowNullValueReturnedForGetOnlyCollectionExceptionMethod, type);
                        _ilg.EndIf();
                    }

                    ReadSimpleDictionary(collectionContract, itemType);

                    _ilg.Call(_contextArg, XmlFormatGeneratorStatics.CheckEndOfArrayMethod, _xmlReaderArg, size, _memberNamesArg, _emptyDictionaryStringArg);

                    _ilg.Else();
                }

                //check that items are actually going to be deserialized into the collection
                IsStartElement(_memberNamesArg, _emptyDictionaryStringArg);
                _ilg.If();

                if (!type.GetTypeInfo().IsValueType)
                {
                    _ilg.If(_objectLocal, Cmp.EqualTo, null);
                    _ilg.Call(null, XmlFormatGeneratorStatics.ThrowNullValueReturnedForGetOnlyCollectionExceptionMethod, type);
                    _ilg.EndIf();
                }

                if (isArray)
                {
                    _ilg.Load(_objectLocal);
                    _ilg.Call(XmlFormatGeneratorStatics.GetArrayLengthMethod);
                    _ilg.Stloc(size);
                }

                LocalBuilder i = _ilg.DeclareLocal(Globals.TypeOfInt, "i");
                object forLoop = _ilg.For(i, 0, Int32.MaxValue);
                IsStartElement(_memberNamesArg, _emptyDictionaryStringArg);
                _ilg.If();
                _ilg.Call(_contextArg, XmlFormatGeneratorStatics.IncrementItemCountMethod, 1);
                LocalBuilder value = ReadCollectionItem(collectionContract, itemType);
                if (isArray)
                {
                    _ilg.If(size, Cmp.EqualTo, i);
                    _ilg.Call(null, XmlFormatGeneratorStatics.ThrowArrayExceededSizeExceptionMethod, size, type);
                    _ilg.Else();
                    _ilg.StoreArrayElement(_objectLocal, i, value);
                    _ilg.EndIf();
                }
                else
                    StoreCollectionValue(_objectLocal, value, collectionContract);
                _ilg.Else();
                IsEndElement();
                _ilg.If();
                _ilg.Break(forLoop);
                _ilg.Else();
                HandleUnexpectedItemInCollection(i);
                _ilg.EndIf();
                _ilg.EndIf();
                _ilg.EndFor();
                _ilg.Call(_contextArg, XmlFormatGeneratorStatics.CheckEndOfArrayMethod, _xmlReaderArg, size, _memberNamesArg, _emptyDictionaryStringArg);

                _ilg.EndIf();

                if (canReadSimpleDictionary)
                {
                    _ilg.EndIf();
                }
            }