System.Runtime.Serialization.XmlFormatReaderGenerator.XmlFormatReaderGenerator.CriticalHelper.ReadValue C# (CSharp) Method

            private LocalBuilder ReadValue(Type type, string name, string ns)
            {
                LocalBuilder value = _ilg.DeclareLocal(type, "valueRead");
                LocalBuilder nullableValue = null;
                int nullables = 0;
                while (type.GetTypeInfo().IsGenericType && type.GetGenericTypeDefinition() == Globals.TypeOfNullable)
                {
                    nullables++;
                    type = type.GetGenericArguments()[0];
                }

                PrimitiveDataContract primitiveContract = PrimitiveDataContract.GetPrimitiveDataContract(type);
                if ((primitiveContract != null && primitiveContract.UnderlyingType != Globals.TypeOfObject) || nullables != 0 || type.GetTypeInfo().IsValueType)
                {
                    LocalBuilder objectId = _ilg.DeclareLocal(Globals.TypeOfString, "objectIdRead");
                    _ilg.Call(_contextArg, XmlFormatGeneratorStatics.ReadAttributesMethod, _xmlReaderArg);
                    _ilg.Call(_contextArg, XmlFormatGeneratorStatics.ReadIfNullOrRefMethod, _xmlReaderArg, type, DataContract.IsTypeSerializable(type));
                    _ilg.Stloc(objectId);
                    // Deserialize null
                    _ilg.If(objectId, Cmp.EqualTo, Globals.NullObjectId);
                    if (nullables != 0)
                    {
                        _ilg.LoadAddress(value);
                        _ilg.InitObj(value.LocalType);
                    }
                    else if (type.GetTypeInfo().IsValueType)
                        ThrowValidationException(SR.Format(SR.ValueTypeCannotBeNull, DataContract.GetClrTypeFullName(type)));
                    else
                    {
                        _ilg.Load(null);
                        _ilg.Stloc(value);
                    }

                    // Deserialize value

                    // Compare against Globals.NewObjectId, which is set to string.Empty
                    _ilg.ElseIfIsEmptyString(objectId);
                    _ilg.Call(_contextArg, XmlFormatGeneratorStatics.GetObjectIdMethod);
                    _ilg.Stloc(objectId);
                    if (type.GetTypeInfo().IsValueType)
                    {
                        _ilg.IfNotIsEmptyString(objectId);
                        ThrowValidationException(SR.Format(SR.ValueTypeCannotHaveId, DataContract.GetClrTypeFullName(type)));
                        _ilg.EndIf();
                    }
                    if (nullables != 0)
                    {
                        nullableValue = value;
                        value = _ilg.DeclareLocal(type, "innerValueRead");
                    }

                    if (primitiveContract != null && primitiveContract.UnderlyingType != Globals.TypeOfObject)
                    {
                        _ilg.Call(_xmlReaderArg, primitiveContract.XmlFormatReaderMethod);
                        _ilg.Stloc(value);
                        if (!type.GetTypeInfo().IsValueType)
                            _ilg.Call(_contextArg, XmlFormatGeneratorStatics.AddNewObjectMethod, value);
                    }
                    else
                    {
                        InternalDeserialize(value, type, name, ns);
                    }
                    // Deserialize ref
                    _ilg.Else();
                    if (type.GetTypeInfo().IsValueType)
                        ThrowValidationException(SR.Format(SR.ValueTypeCannotHaveRef, DataContract.GetClrTypeFullName(type)));
                    else
                    {
                        _ilg.Call(_contextArg, XmlFormatGeneratorStatics.GetExistingObjectMethod, objectId, type, name, ns);
                        _ilg.ConvertValue(Globals.TypeOfObject, type);
                        _ilg.Stloc(value);
                    }
                    _ilg.EndIf();

                    if (nullableValue != null)
                    {
                        _ilg.If(objectId, Cmp.NotEqualTo, Globals.NullObjectId);
                        WrapNullableObject(value, nullableValue, nullables);
                        _ilg.EndIf();
                        value = nullableValue;
                    }
                }
                else
                {
                    InternalDeserialize(value, type, name, ns);
                }

                return value;
            }