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c# - 为什么 XmlSerializer 在映射具有相同名称但不同命名空间的类的对象图时无法初始化？

coder 2024-07-02 原文

我从没有 namespace 的第三方接收 XML。 XML 模式以简化和混淆的形式显示如下:

<Root>
    <Address>
        <PostalCode>57373</PostalCode>
    </Address>
    <ReportAReport>
        <Address>
            <Zip>18573</Zip>
        </Address>
    </ReportAReport>
</Root>

请注意这里有两个不同的 Address 类。它们实际上被定义为两个不同的 complexType，每个都在我从第三方收到的单独的 XML 模式中。一种模式反射(reflect)了 Root 模型，而另一种模式反射(reflect)了 ReportAReport 的模型。每个 Address 类都有不同的属性。

我在命名空间中表示每一个，将每个 XML 模式视为其自己的命名空间。事实上，模式定义了 namespace ，但我从第三方收到的 XML 响应出于某种原因选择省略这些 namespace 。

命名空间:MyCompany.MyProject

namespace MyCompany.MyProject
{
    public class Root
    {
        public Address Address { get; set; }
        public ReportAReport ReportAReport { get; set; }
    }

    public class Address
    {
        public string PostalCode { get; set; }
    }
}

命名空间:MyCompany.MyProject.ReportA

namespace MyCompany.MyProject.ReportA
{
    public class ReportAReport
    {
        public Address Address { get; set; }
    }

    public class Address
    {
        public string Zip { get; set; }
    }
}

我得到的异常如下:

Result Message: Unable to create instance of class MyCompany.MyProject.Test.AggregatorTests. Error: System.TypeInitializationException: The type initializer for 'MyCompany.MyProject.Test.AggregatorTests' threw an exception. ---> System.InvalidOperationException: There was an error reflecting type 'MyCompany.MyProject.Root'. ---> System.InvalidOperationException: There was an error reflecting property 'ReportAReport'. ---> System.InvalidOperationException: There was an error reflecting type 'MyCompany.MyProject.ReportA.ReportAReport'. ---> System.InvalidOperationException: There was an error reflecting property 'Address'. ---> System.InvalidOperationException: There was an error reflecting type 'MyCompany.MyProject.ReportA.Address'. ---> System.InvalidOperationException: Types 'MyCompany.MyProject.ReportA.Address' and 'MyCompany.MyProject.Address' both use the XML type name, 'Address', from namespace ''. Use XML attributes to specify a unique XML name and/or namespace for the type..

此异常所指的行如下:

XmlSerializer serializer = new XmlSerializer(typeof(Root));

异常似乎很清楚发生了什么。 XmlSerializer 无法理解将 ReportAReport 类中的属性“Address”映射到哪个 Address 类。

我不明白的是为什么它无法理解将属性映射到哪个 Address 类。在 ReportAReport 的类定义中，“Address”属性声明为 MyCompany.MyProject.ReportA.Address 类型。

我什至尝试使用 XmlElementAttribute 在 ReportAReport 上指定 Type:

[XmlElement(Type = typeof(Address))]
public Address Address { get; set; }

不过，无论如何，这似乎相当多余......

问题

编译器很清楚这里的Address指的是MyCompany.MyProject.ReportA.Address。为什么 XmlSerializer 无法做出这种识别？

XmlSerializer 不应该知道如果它在 ReportAReport 节点中遇到 Address 节点，它是 MyCompany 类型.MyProject.ReportA.Address 而不是 MyCompany.MyProject.Address？

我在这里错过了什么？

我添加了堆栈跟踪，因为它显示了 XmlSerializer 初始化过程出现问题的位置。我实际上从我的真实示例中提取了这个堆栈跟踪，它有几个比示例更深的节点，所以堆栈跟踪中可能有一些递归级别似乎与我的示例代码不一致提供。

Result StackTrace:  
at System.Xml.Serialization.XmlReflectionImporter.GetTypeMapping(String typeName, String ns, TypeDesc typeDesc, NameTable typeLib, Type type)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.CreateArrayElementsFromAttributes(ArrayMapping arrayMapping, XmlArrayItemAttributes attributes, Type arrayElementType, String arrayElementNs, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportArrayLikeMapping(ArrayModel model, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.CreateArrayElementsFromAttributes(ArrayMapping arrayMapping, XmlArrayItemAttributes attributes, Type arrayElementType, String arrayElementNs, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportArrayLikeMapping(ArrayModel model, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportAccessorMapping(MemberMapping accessor, FieldModel model, XmlAttributes a, String ns, Type choiceIdentifierType, Boolean rpc, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportFieldMapping(StructModel parent, FieldModel model, XmlAttributes a, String ns, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.InitializeStructMembers(StructMapping mapping, StructModel model, Boolean openModel, String typeName, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportStructLikeMapping(StructModel model, String ns, Boolean openModel, XmlAttributes a, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
 --- End of inner exception stack trace ---
    at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(TypeModel model, String ns, ImportContext context, String dataType, XmlAttributes a, Boolean repeats, Boolean openModel, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportElement(TypeModel model, XmlRootAttribute root, String defaultNamespace, RecursionLimiter limiter)
   at System.Xml.Serialization.XmlReflectionImporter.ImportTypeMapping(Type type, XmlRootAttribute root, String defaultNamespace)
   at System.Xml.Serialization.XmlSerializer..ctor(Type type, String defaultNamespace)
   at System.Xml.Serialization.XmlSerializer..ctor(Type type)
   at MyCompany.MyProject.Test.AggregatorTests..cctor() in c:\Users\crush\Documents\Visual Studio 2012\Projects\MyCompany.MyProject\Test\MyCompany.MyProject.Test\AggregatorTests.cs:line 16
 --- End of inner exception stack trace ---
    at MyCompany.MyProject.Test.AggregatorTests..ctor()

更新:在意识到我对收到的异常的初步评估完全不正确后，我完全重写了这个问题。我疏忽地认为反序列化是我收到异常的原因，而事实上，它明确指出 XmlSerializer 的初始化是问题所在。该问题已被编辑以说明这一事实，我们说话时我正在擦掉脸上的蛋糕。对于因最初的错误和不完整信息而误导的任何人，我深表歉意。

最佳答案

尝试将此模型反序列化。您可以实例化任一类型的新地址，并设置反序列化模型中的值。您可以使用 AutoMapper 来完成对象的复制

    /// <remarks/>
    [System.SerializableAttribute()]
    [System.ComponentModel.DesignerCategoryAttribute("code")]
    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
    [System.Xml.Serialization.XmlRootAttribute(Namespace = "", IsNullable = false)]
    public partial class Root
    {

        private RootAddress addressField;

        private RootReportAReport reportAReportField;

        /// <remarks/>
        public RootAddress Address
        {
            get
            {
                return this.addressField;
            }
            set
            {
                this.addressField = value;
            }
        }

        /// <remarks/>
        public RootReportAReport ReportAReport
        {
            get
            {
                return this.reportAReportField;
            }
            set
            {
                this.reportAReportField = value;
            }
        }
    }

    /// <remarks/>
    [System.SerializableAttribute()]
    [System.ComponentModel.DesignerCategoryAttribute("code")]
    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
    public partial class RootAddress
    {

        private ushort postalCodeField;

        /// <remarks/>
        public ushort PostalCode
        {
            get
            {
                return this.postalCodeField;
            }
            set
            {
                this.postalCodeField = value;
            }
        }
    }

    /// <remarks/>
    [System.SerializableAttribute()]
    [System.ComponentModel.DesignerCategoryAttribute("code")]
    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
    public partial class RootReportAReport
    {

        private RootReportAReportAddress addressField;

        /// <remarks/>
        public RootReportAReportAddress Address
        {
            get
            {
                return this.addressField;
            }
            set
            {
                this.addressField = value;
            }
        }
    }

    /// <remarks/>
    [System.SerializableAttribute()]
    [System.ComponentModel.DesignerCategoryAttribute("code")]
    [System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
    public partial class RootReportAReportAddress
    {

        private ushort zipField;

        /// <remarks/>
        public ushort Zip
        {
            get
            {
                return this.zipField;
            }
            set
            {
                this.zipField = value;
            }
        }
    }

关于c# - 为什么 XmlSerializer 在映射具有相同名称但不同命名空间的类的对象图时无法初始化？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/23248906/

c#XmlSerializerXmlReflectionImporterSerializationRecursionLimiterxml

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