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

            private void ReadSimpleDictionary(CollectionDataContract collectionContract, Type keyValueType)
            {
                Type[] keyValueTypes = keyValueType.GetGenericArguments();
                Type keyType = keyValueTypes[0];
                Type valueType = keyValueTypes[1];

                int keyTypeNullableDepth = 0;
                Type keyTypeOriginal = keyType;
                while (keyType.GetTypeInfo().IsGenericType && keyType.GetGenericTypeDefinition() == Globals.TypeOfNullable)
                {
                    keyTypeNullableDepth++;
                    keyType = keyType.GetGenericArguments()[0];
                }

                ClassDataContract keyValueDataContract = (ClassDataContract)collectionContract.ItemContract;
                DataContract keyDataContract = keyValueDataContract.Members[0].MemberTypeContract;

                KeyParseMode keyParseMode = KeyParseMode.Fail;

                if (keyType == Globals.TypeOfString || keyType == Globals.TypeOfObject)
                {
                    keyParseMode = KeyParseMode.AsString;
                }
                else if (keyType.GetTypeInfo().IsEnum)
                {
                    keyParseMode = KeyParseMode.UsingParseEnum;
                }
                else if (keyDataContract.ParseMethod != null)
                {
                    keyParseMode = KeyParseMode.UsingCustomParse;
                }

                if (keyParseMode == KeyParseMode.Fail)
                {
                    ThrowSerializationException(
                        SR.Format(
                            SR.KeyTypeCannotBeParsedInSimpleDictionary,
                                DataContract.GetClrTypeFullName(collectionContract.UnderlyingType),
                                DataContract.GetClrTypeFullName(keyType)));
                }
                else
                {
                    LocalBuilder nodeType = _ilg.DeclareLocal(typeof(XmlNodeType), "nodeType");

                    _ilg.BeginWhileCondition();
                    _ilg.Call(_xmlReaderArg, JsonFormatGeneratorStatics.MoveToContentMethod);
                    _ilg.Stloc(nodeType);
                    _ilg.Load(nodeType);
                    _ilg.Load(XmlNodeType.EndElement);
                    _ilg.BeginWhileBody(Cmp.NotEqualTo);

                    _ilg.Load(nodeType);
                    _ilg.Load(XmlNodeType.Element);
                    _ilg.If(Cmp.NotEqualTo);
                    ThrowUnexpectedStateException(XmlNodeType.Element);
                    _ilg.EndIf();

                    _ilg.Call(_contextArg, XmlFormatGeneratorStatics.IncrementItemCountMethod, 1);

                    if (keyParseMode == KeyParseMode.UsingParseEnum)
                    {
                        _ilg.Load(keyType);
                    }

                    _ilg.Load(_xmlReaderArg);
                    _ilg.Call(JsonFormatGeneratorStatics.GetJsonMemberNameMethod);

                    if (keyParseMode == KeyParseMode.UsingParseEnum)
                    {
                        _ilg.Call(JsonFormatGeneratorStatics.ParseEnumMethod);
                        _ilg.ConvertValue(Globals.TypeOfObject, keyType);
                    }
                    else if (keyParseMode == KeyParseMode.UsingCustomParse)
                    {
                        _ilg.Call(keyDataContract.ParseMethod);
                    }
                    LocalBuilder pairKey = _ilg.DeclareLocal(keyType, "key");
                    _ilg.Stloc(pairKey);
                    if (keyTypeNullableDepth > 0)
                    {
                        LocalBuilder pairKeyNullable = _ilg.DeclareLocal(keyTypeOriginal, "keyOriginal");
                        WrapNullableObject(pairKey, pairKeyNullable, keyTypeNullableDepth);
                        pairKey = pairKeyNullable;
                    }

                    LocalBuilder pairValue = ReadValue(valueType, String.Empty);
                    StoreKeyValuePair(_objectLocal, collectionContract, pairKey, pairValue);

                    _ilg.EndWhile();
                }
            }