Web服务中的循环引用

Question

我正在尝试解决 Web 服务中的循环引用。该解决方案构建良好，并且一些操作是可调用的，但是使用引用类型的操作会产生循环引用异常（如下）。

System.InvalidOperationException: There was an error generating the XML document. ---> System.InvalidOperationException: A circular reference was detected while serializing an object of type MyCoreAssembly.MyType <-------- this is the referenced type
   at System.Xml.Serialization.XmlSerializationWriter.WriteStartElement(String name, String ns, Object o, Boolean writePrefixed, XmlSerializerNamespaces xmlns)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write21_VRD(String n, String ns, VRD o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write21_VRD(String n, String ns, VRD o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write31_Hereditament(String n, String ns, Hereditament o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write32_HereditamentVrd(String n, String ns, HereditamentVrd o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write33_VRDResponse(String n, String ns, VRDResponse o, Boolean isNullable, Boolean needType)
   at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriter1.Write43_VRDResponse(Object o)
   at Microsoft.Xml.Serialization.GeneratedAssembly.VRDResponseSerializer.Serialize(Object objectToSerialize, XmlSerializationWriter writer)  <------- this is my type
   at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id)
   --- End of inner exception stack trace ---
   at System.Xml.Serialization.XmlSerializer.Serialize(XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, String encodingStyle, String id)
   at System.Xml.Serialization.XmlSerializer.Serialize(TextWriter textWriter, Object o, XmlSerializerNamespaces namespaces)
   at System.Web.Services.Protocols.XmlReturnWriter.Write(HttpResponse response, Stream outputStream, Object returnValue)
   at System.Web.Services.Protocols.HttpServerProtocol.WriteReturns(Object[] returnValues, Stream outputStream)
   at System.Web.Services.Protocols.WebServiceHandler.WriteReturns(Object[] returnValues)
   at System.Web.Services.Protocols.WebServiceHandler.Invoke()

架构大致如下：

Core layer <------ Data Layer <----- Logic Layer <---------- Web service
                     \/--------------------\/ <-------------------|
                                            \/--------------------|

每一层都是一个单独的程序集，Web 服务引用所有三个程序集。我已经附加了一个调试器，但它不会中断。看起来内部结构正在失败，但我不知道一切都在哪里构建。我该如何调试呢？

Answer 1

您的循环引用不在项目文件中，而是在您尝试通过网络服务发送的对象中。你们中的一个对象具有对自身的引用或引用该对象的对象。

错误消息告诉您查看您的类型：MyCoreAssembly.MyType