C# .NET XML序列化错误：选择标识符的值无效或缺失

以下说明来自：

我尝试用XmlChoiceIdentifier属性序列化对象数组。但是很明显，序列化程序需要一个数组，而ObservableCollection将导致序列化程序抛出并出错（第一个链接）。我真的需要有一个ObservableCollection来保持UI的更新。因此，我试图让序列化引擎访问数组，而UI将以浪费资源的方式访问可观察的集合albiet

这是我的“解决方案”

使用此解决方案，我得到以下错误：

System.InvalidOperationException occurred


HResult=-2146233079
  Message=There was an error generating the XML document.
  Source=System.Xml
  StackTrace:
       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.Xml.Serialization.XmlSerializer.Serialize(TextWriter textWriter, Object o)
       at Otometrics.ICSSuite.Reports.ViewModel.EditReportVM.<InitializeCommands>b__38(Object o) in 
  InnerException: System.InvalidOperationException
       HResult=-2146233079
       Message=Invalid or missing value of the choice identifier 'ItemTypeArray' of type 'ItemChoiceType[]'.
       Source=Microsoft.GeneratedCode
       StackTrace:
            at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterCustomReportList.Write4_GroupAndItemsCollection(String n, String ns, GroupAndItemsCollection o, Boolean isNullable, Boolean needType)

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尽管有一些关于此错误消息的正确答案。他们都没有工作。我希望我能获得荣誉，但唉，我真正聪明的团队领导发现了这一点。我的代码所发生的事情是，我们使用xsd2code为具有xmlChoiceIdentifier的模式生成vb。在我们的业务类中，当我们循环代码时，ItemChoiceType的对象在循环之外。因此，在验证xml时，第一个节点是好的，之后的每个节点都不好。虽然我有一个ItemsElementName，它有一个很好的值，但它只是一次迭代，其余的xml验证都会因为这个错误而失败

在创建xml和Viola时，我们在循环中移动了ItemsChoiceType！希望这有帮助。它可能与此堆栈溢出中的修复程序无关，但如果您的问题与我们的问题相同，它会给出相同的错误。您将看到这一页

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快乐编码：）

使用时的问题！[XSD2代码与节点枚举有关。是的，它读取第一个节点，然后在其他节点上失败。对我来说，在我将GenerateOrderXmlAttributes和GenerateXMLAttributes更改为true并将CollectionObject类型更改为Array后，它就起作用了

using (StreamWriter writer = new StreamWriter(dlg.FileName))
                    {
                        ItemChoiceType[] ic = new ItemChoiceType[]
                        {
                            ItemChoiceType.Item, 
                            ItemChoiceType.Macro
                        };
                        XmlSerializer xml = null;

                                group.ItemTypeArray = ic;
                            xml = new XmlSerializer(typeof(GroupAndItemsCollection));
                            xml.Serialize(writer, group);



                        writer.Close();
                    }

System.InvalidOperationException occurred


HResult=-2146233079
  Message=There was an error generating the XML document.
  Source=System.Xml
  StackTrace:
       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.Xml.Serialization.XmlSerializer.Serialize(TextWriter textWriter, Object o)
       at Otometrics.ICSSuite.Reports.ViewModel.EditReportVM.<InitializeCommands>b__38(Object o) in 
  InnerException: System.InvalidOperationException
       HResult=-2146233079
       Message=Invalid or missing value of the choice identifier 'ItemTypeArray' of type 'ItemChoiceType[]'.
       Source=Microsoft.GeneratedCode
       StackTrace:
            at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationWriterCustomReportList.Write4_GroupAndItemsCollection(String n, String ns, GroupAndItemsCollection o, Boolean isNullable, Boolean needType)

[XmlType(IncludeInSchema = false)]
public enum ItemChoiceType
{
    [XmlEnumAttribute("Item")]
    Item,
    [XmlEnumAttribute("Macro")]
    Macro
}

[Serializable()]
public class GroupAndItemsCollection
{
    [XmlElementAttribute(IsNullable = false)]
    [XmlIgnore]
    public ItemChoiceType[] ItemTypeArray;

    [XmlAttribute(AttributeName = "name")]
    public string Group
    {
        get { return m_Group; }
        set
        {
            if (m_Group == value)
                return;
            m_Group = value;
            //OnPropertyChanged("Group");
        }
    }

    private ListItemName[] m_itemsArray;

[XmlChoiceIdentifier("ItemTypeArray")]
    [XmlElement(ElementName = "Item", Type = typeof(ObservableCollection<ListItemName>))]
    [XmlElement(ElementName = "Macro", Type = typeof(ObservableCollection<ListItemName>))]
    public ListItemName[] ItemsArray
    {
        get { return m_itemsArray; }
        set { m_itemsArray = value; }
    }


    public GroupAndItemsCollection()
    {
        IsExpanded = true;
    }
}

Message=Invalid or missing value of the choice identifier 'ItemTypeArray' of type 'ItemChoiceType[]'.