XML子元素反序列化抛出InvalidOperationException
本文关键字：InvalidOperationException 反序列化 元素 XML | 更新日期: 2023-09-27 18:09:43
我试图手动反序列化数据对象的层次结构(完整的代码在下面)，但得到一个异常我不明白。
-
DEMDataSet包含DemographicReportGroup对象的集合。 -
DemographicReportGroup实现IXmlSerializable，包含Agency对象 -
Agency对象包含叶子数据项dAgency.01，即EMSAgencyUniqueStateID。
我正在为DemographicReportGroup实现ReadXml方法，但我得到一个异常抛出如下:
#region ReadXml
public void ReadXml(System.Xml.XmlReader xmlReader)
{
xmlReader.MoveToContent();
this.timeStamp = DateTime.Parse(xmlReader.GetAttribute("timeStamp"));
if (xmlReader.IsEmptyElement) return;
xmlReader.ReadStartElement();
if (xmlReader.Name == "dAgency")
{
xmlReader.ReadStartElement("dAgency");
// **Exception here: System.InvalidOperationException**
this.Agency = new XmlSerializer(typeof(Agency)).Deserialize(xmlReader) as Agency;
xmlReader.ReadEndElement();
}
xmlReader.ReadEndElement();
}
#endregion
系统。InvalidOperationException: & lt; dAgency。01 xmlns='http://www.nemsis.org'>不符合预期。
到目前为止，我发现的所有代码样本都表明这应该可以工作…也许是XML属性配置错误?
希望有人能帮忙!
另外，如果你好奇的话:
- 你为什么要实现
IXmlSerializable?-
timeStamp属性是日期/时间。如果它是一个普通的DateTime，那么在序列化时它总是有一个值(1/1/0001)。DateTime?类型让我知道它什么时候没有值，但它不能被序列化为属性。这个例子属于的数据标准规定时间戳必须是一个属性。
-
- 如何实现ShouldSerializetimeStampValue?
- 这将产生一个额外的属性和额外的方法(timeStampValue和ShouldSerializetimeStampValue)，对于一个数据项来说，这是太多的代码了。此外，这不是我要处理的唯一时间戳。
完整代码(作为Visual Studio的单元测试):
using System;
using System.Collections.Generic;
using System.IO;
using System.Xml.Serialization; // System.Xml.dll.
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace Tests.Xml
{
[TestClass]
public class TestIXmlSerializable
{
[TestMethod]
public void DeserializeChildElement()
{
var xml = @"<DEMDataSet xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xsi:schemaLocation=""http://www.nemsis.org http://nemsis.org/media/XSD_v3/_nemsis_v3.3.1/3.3.1.130201/XSDs/NEMSIS_XSDs_v3.3.1.130201/DEMDataSet_v3.xsd"" xmlns=""http://www.nemsis.org"">
<DemographicReport timeStamp=""1969-03-14T07:38:20+07:00"">
<dAgency>
<dAgency.01>M</dAgency.01>
</dAgency>
</DemographicReport>
</DEMDataSet>";
var xmlSerializer = new XmlSerializer(typeof(DEMDataSet));
DEMDataSet demDataSet = null;
using (var streamReader = new StringReader(xml))
demDataSet = xmlSerializer.Deserialize(streamReader) as DEMDataSet;
}
}
[Serializable]
/// <summary>Root Tag For Demographic DataSet</summary>
[XmlType(AnonymousType = true, Namespace = "http://www.nemsis.org")]
[XmlRoot(Namespace = "http://www.nemsis.org", IsNullable = false)]
public partial class DEMDataSet
{
#region DemographicReportGroup
private List<DemographicReportGroup> _demographicReportGroup;
/// <summary>Container Tag to hold each instance of a demographic record</summary>
[XmlElement("DemographicReport")]
public List<DemographicReportGroup> DemographicReportGroup
{
get
{
return this._demographicReportGroup;
}
set
{
this._demographicReportGroup = value;
}
}
#endregion
}
[Serializable]
public partial class DemographicReportGroup : IXmlSerializable
{
#region Agency
private Agency _agency;
/// <summary></summary>
[XmlElement("dAgency", IsNullable = false)]
public Agency Agency
{
get
{
return this._agency;
}
set
{
this._agency = value;
}
}
#endregion
#region timeStamp
private DateTime? _timeStamp;
/// <summary></summary>
[XmlAttribute]
public DateTime? timeStamp
{
get
{
return this._timeStamp;
}
set
{
this._timeStamp = value;
}
}
#endregion
#region GetSchema
public System.Xml.Schema.XmlSchema GetSchema()
{
return null;
}
#endregion
#region ReadXml
public void ReadXml(System.Xml.XmlReader xmlReader)
{
xmlReader.MoveToContent();
this.timeStamp = DateTime.Parse(xmlReader.GetAttribute("timeStamp"));
if (xmlReader.IsEmptyElement) return;
xmlReader.ReadStartElement();
if (xmlReader.Name == "dAgency") { xmlReader.ReadStartElement("dAgency"); this.Agency = new XmlSerializer(typeof(Agency)).Deserialize(xmlReader) as Agency; xmlReader.ReadEndElement(); }
xmlReader.ReadEndElement();
}
#endregion
#region WriteXml
public void WriteXml(System.Xml.XmlWriter xmlWriter)
{
if (this.timeStamp.HasValue) xmlWriter.WriteAttributeString("timeStamp", this.timeStamp.Value.ToString("o"));
if (this.Agency != null) { xmlWriter.WriteStartElement("dAgency"); new XmlSerializer(typeof(Agency)); xmlWriter.WriteEndElement(); }
}
#endregion
}
[Serializable]
/// <summary></summary>
[XmlType(Namespace = "http://www.nemsis.org")]
[XmlRoot(Namespace = "http://www.nemsis.org", IsNullable = true)]
public partial class Agency
{
#region EMSAgencyUniqueStateID
private string _emsAgencyUniqueStateID;
/// <summary>The unique ID assigned to the EMS Agency which is associated with all state licensure numbers and information.</summary>
[XmlElement("dAgency.01")]
public string EMSAgencyUniqueStateID
{
get
{
return this._emsAgencyUniqueStateID;
}
set
{
this._emsAgencyUniqueStateID = value;
}
}
#endregion
}
}
如何使用Linq To Xml
var xml = @"<DEMDataSet xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" xsi:schemaLocation=""http://www.nemsis.org http://nemsis.org/media/XSD_v3/_nemsis_v3.3.1/3.3.1.130201/XSDs/NEMSIS_XSDs_v3.3.1.130201/DEMDataSet_v3.xsd"" xmlns=""http://www.nemsis.org"">
<DemographicReport timeStamp=""1969-03-14T07:38:20+07:00"">
<dAgency>
<dAgency.01>M</dAgency.01>
</dAgency>
</DemographicReport>
</DEMDataSet>";
var xDoc = XDocument.Parse(xml);
XNamespace ns = "http://www.nemsis.org";
var result = xDoc.Descendants(ns + "DemographicReport")
.Select(d => new DemographicReportGroup
{
timeStamp = (DateTime)d.Attribute("timeStamp"),
Agency = new Agency{EMSAgencyUniqueStateID = d.Descendants(ns + "dAgency.01").First().Value}
})
.ToList();
public class DemographicReportGroup
{
public Agency Agency { set; get; }
public DateTime timeStamp;
}
public class Agency
{
public string EMSAgencyUniqueStateID { set; get; }
}