将xml反序列化到对象列表

Question

我在将xml文件反序列化为对象列表时遇到问题。出现的错误是"System.InvalidOperationException：“在XML document (2,2)中有一个错误。InvalidOperationException <Feed xmlns=">不是预期的。在将xml转换为对象时，似乎出现了一些问题。

这个程序似乎中断在：list = (List<object>) loadXML.Deserialize(fs);

public static List<object> deSerialize()
        {

            string path = Environment.CurrentDirectory + "\\xmlfile.xml";
            XmlSerializer loadXML = new XmlSerializer(typeof(List<object>));

            List<object> list = new List<object>();
            if (File.Exists(path))
            {
                using (FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read))
                {
                    list = (List<object>) loadXML.Deserialize(fs);

                    //var lista = (List<object>)obj;

                    return list;
                }
            }
            else
            {
                return new List<object>();
            }
        }

我的xml文件：

<?xml version="1.0"?>
<Feed xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Name>NASA Breaking News</Name>
  <NumberOfEpisodes>10</NumberOfEpisodes>
  <Episodes>
    <Episode>
      <EpisodeNumber>1</EpisodeNumber>
      <Title>NASA Invites Media to Next SpaceX Space Station Cargo Launch</Title>
      <Description>Media accreditation is open for the launch of the next SpaceX delivery of science investigations, supplies, and equipment to the International Space Station.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>2</EpisodeNumber>
      <Title>NASA Administrator Invites Public to Update on Agency’s Return to Moon</Title>
      <Description>The public is invited to join NASA Administrator Jim Bridenstine at 9:40 a.m. EDT Friday, Oct. 25, for an update on the agency’s Artemis program and the critical role international partnerships have in returning astronauts to the Moon and going on to Mars.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>3</EpisodeNumber>
      <Title>Maryland, Washington Students to Speak with NASA Astronaut Aboard Space Station</Title>
      <Description>Students from Maryland and Washington, D.C., will have an opportunity this week to talk with a NASA astronaut currently living and working aboard the International Space Station.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>4</EpisodeNumber>
      <Title>NASA Invites Media to Boeing Starliner Transport to Launch Site</Title>
      <Description>Media accreditation is open for two-days of activities in mid-November for the next milestone in NASA’s Commercial Crew Program, as Boeing’s CST-100 Starliner is transported for integration on a United Launch Alliance (ULA) Atlas V rocket.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>5</EpisodeNumber>
      <Title>NASA to Provide Coverage of Key Events at 70th International Astronautical Congress</Title>
      <Description>NASA will provide live coverage on NASA Television of key events at the 70th International Astronautical Congress (IAC), which takes place Oct. 21-25 at the Walter E. Washington Convention Center in Washington.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>6</EpisodeNumber>
      <Title>In-Space News Conference to Review First All-Woman Spacewalk</Title>
      <Description>NASA astronauts Christina Koch and Jessica Meir will participate in a news conference from orbit at noon EDT, Monday, Oct. 21, following their Friday spacewalk – the first to be conducted by two women.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>7</EpisodeNumber>
      <Title>NASA’s Planetary Protection Review Addresses Changing Reality of Space Exploration</Title>
      <Description>NASA released a report Friday with recommendations from the Planetary Protection Independent Review Board (PPIRB) the agency established in response to a recent National Academies of Sciences, Engineering, and Medicine report and a recommendation from the NASA Advisory Council.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>8</EpisodeNumber>
      <Title>NASA to Televise First All-Female Spacewalk, Host Media Teleconference</Title>
      <Description>On the first ever all-female spacewalk, NASA astronauts Christina Koch and Jessica Meir will venture outside the International Space Station about 7:50 a.m. EDT Friday, Oct. 18, to replace faulty equipment on the station’s exterior. Live coverage will begin at 6:30 a.m. on NASA Television and the agency’s website.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>9</EpisodeNumber>
      <Title>NASA Invites Media to Launch of Solar Orbiter Spacecraft</Title>
      <Description>NASA has opened media accreditation for the Feb. 5, 2020, launch of Solar Orbiter – a joint NASA/ESA (European Space Agency) mission that will address central questions concerning our star, the Sun.</Description>
    </Episode>
    <Episode>
      <EpisodeNumber>10</EpisodeNumber>
      <Title>NASA to Discuss Planetary Protection Review’s Findings and Recommendations</Title>
      <Description>NASA will host a media teleconference at 3:30 p.m. EDT Friday, Oct. 18, to discuss recommendations presented by the Planetary Protection Independent Review Board (PPIRB), established in June 2019 by Thomas Zurbuchen, associate administrator for the agency’s Science Mission Directorate.</Description>
    </Episode>
  </Episodes>
</Feed>

Answer 1

您需要从定义对XML建模的类型开始。我通过在Visual Studio中复制您的XML，然后转到Edit -> Paste Special -> Paste XML As Classes (并手动整理结果)来生成它们，但您也可以手动编写它们(使用this document，特别是this section作为引用)或使用xsd.exe。

public class Feed
{
    public string Name { get; set; }

    public byte NumberOfEpisodes { get; set; }

    [XmlArrayItem("Episode")]
    public List<Episode> Episodes { get; set; }
}

public class Episode
{
    public byte EpisodeNumber { get; set; }

    public string Title { get; set; }

    public string Description { get; set; }
}

然后，您可以：

var serializer = new XmlSerializer(typeof(Feed));
var feed = (Feed)serializer.Deserialize(fs);

Answer 2

您必须定义System.Xml.Serialization.XmlSerializer可以序列化的对象的类型。示例：

var xs = new XmlSerializer(typeof(MyType));
return (MyType)xs.Deserialize(new StringReader(myXmlString));