无法将通用记录转换为对象

Question

您好，我在 c# 中有以下模型。这些是 Avro 文件。

public ProductMessageEvents GetValue(TestPayload parameter)
{
    return new ProductMessageEvents()
        {
            Metadata = new KafkaProductEvent.Metadata
                {
                    Timestamp = "test",
                    Environment = "test"
                },
            Product = new KafkaProductEvent.Product
                {
                    AgeGrading = "test",
                    KeycodeType = "type1",
                    FamilyTree = new KafkaProductEvent.FamilyTree
                        {
                            Class = new KafkaProductEvent.CodeNamePair
                                {
                                    Code = "test code",
                                    Name = "test name"
                                }
                        },
                    DssProduct = new KafkaProductEvent.DssProduct
                        {
                            DocumentStatus = "active"
                        }
                      Options = new Option[]
            {
              new Option
              {
                PrimaryColour = new CodeNamePair
                {
                  Name = "White",
                },
                SecondaryColour = new CodeNamePair
                {
                  Name = "red",
                }
              },
              new Option
              {
                PrimaryColour = new CodeNamePair
                {
                  Name = "White",
                }
              },
                },
            Version = "latestVersion"
        };
    }
}

如果我尝试访问以下值，它会起作用。

 object ageGrading = ((GenericRecord)response.Message.Value["Product"])["AgeGrading"];

如果我尝试访问以下值，则会抛出

object familyTree = ((GenericRecord)response.Message.Value["Product"])["FamilyTree"]["Class"]["Code"];

它抛出错误Cannot apply indexing with [] to an expression of type object

有人可以帮我找出这个错误吗？任何帮助，将不胜感激。谢谢。

Answer 1

您正在将此对象转换为 GenericRecord ((GenericRecord)response.Message.Value["Product"])，但它会将此 ((GenericRecord)response.Message.Value["Product"])["FamilyTree"] 作为对象返回。您需要将每个级别转换为 GenericRecord 以获取其属性。

((GenericRecord)((GenericRecord)((GenericRecord)response.Message.Value["Product"])["FamilyTree"])["Class"])["Code"]