使用XmlReader和类从xsd.exe反序列化Xml

Question

好的，我在尝试学习XmlSerializer时遇到了一个障碍，同时通过一些教程。我遵循了所有推荐的步骤，但我的程序没有返回任何东西，或者返回null。我创建了一个如下的XML文件:

<?xml version='1.0' encoding='UTF-8' ?>
<WeeklyJobs>
   <DailyJobs Date = "02/03/2012"/>
  <DailyJobs Date = "02/04/2012" TotalJobs = "2">
    <Jobs>
      <Job JobName = "Job Name" Description = "Description"/>
      <Job JobName = "Job Name" Description = "Description"/>
    </Jobs>
  </DailyJobs>
  <DailyJobs Date = "02/05/2012" TotalJobs = "1">
    <Jobs>
      <Job JobName = "Job Name" Description = "Description"/>
    </Jobs>
  </DailyJobs>
  <DailyJobs Date = "02/06/2012" TotalJobs = "2">
    <Jobs>
      <Job JobName = "Job Name" Description = "Description"/>
      <Job JobName = "Job Name" Description = "Description"/>
    </Jobs>
  </DailyJobs>
  <DailyJobs Date = "02/07/2012"/>
  <DailyJobs Date = "02/08/2012" TotalJobs = "2">
    <Jobs>
      <Job JobName = "Job Name" Description = "Description"/>
      <Job JobName = "Job Name" Description = "Description"/>
    </Jobs>
  </DailyJobs>
</WeeklyJobs>

然后使用xsd.exe生成。xsd文件，即:

<?xml version="1.0" encoding="utf-8"?>
<xs:schema id="WeeklyJobs" xmlns="" xmlns:xs="http://www.w3.org/2001/XMLSchema"     xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
  <xs:element name="WeeklyJobs" msdata:IsDataSet="true" msdata:UseCurrentLocale="true">
    <xs:complexType>
      <xs:choice minOccurs="0" maxOccurs="unbounded">
        <xs:element name="DailyJobs">
          <xs:complexType>
            <xs:sequence>
              <xs:element name="Jobs" minOccurs="0" maxOccurs="unbounded">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="Job" minOccurs="0" maxOccurs="unbounded">
                      <xs:complexType>
                        <xs:attribute name="JobName" type="xs:string" />
                        <xs:attribute name="Description" type="xs:string" />
                      </xs:complexType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
            <xs:attribute name="Date" type="xs:string" />
            <xs:attribute name="TotalJobs" type="xs:string" />
          </xs:complexType>
        </xs:element>
      </xs:choice>
    </xs:complexType>
  </xs:element>
</xs:schema>

创建模式后，我再次使用xsd.exe为我自动生成类，这是:

/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
[System.Xml.Serialization.XmlRootAttribute(Namespace = "", IsNullable = false)]
public partial class WeeklyJobs
{
    private WeeklyJobsDailyJobs[] itemsField;
    /// <remarks/>
    [System.Xml.Serialization.XmlElementAttribute("DailyJobs", Form = System.Xml.Schema.XmlSchemaForm.Unqualified)]
    public WeeklyJobsDailyJobs[] Items
    {
        get
        {
            return this.itemsField;
        }
        set
        {
            this.itemsField = value;
        }
    }
}
/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
public partial class WeeklyJobsDailyJobs
{
    private WeeklyJobsDailyJobsJobsJob[][] jobsField;
    private string dateField;
    private string totalJobsField;
    /// <remarks/>
    [System.Xml.Serialization.XmlArrayAttribute(Form = System.Xml.Schema.XmlSchemaForm.Unqualified)]
    [System.Xml.Serialization.XmlArrayItemAttribute("Job", typeof(WeeklyJobsDailyJobsJobsJob), Form = System.Xml.Schema.XmlSchemaForm.Unqualified, IsNullable = false)]
    public WeeklyJobsDailyJobsJobsJob[][] Jobs
    {
        get
        {
            return this.jobsField;
        }
        set
        {
            this.jobsField = value;
        }
    }
    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute()]
    public string Date
    {
        get
        {
            return this.dateField;
        }
        set
        {
            this.dateField = value;
        }
    }
    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute()]
    public string TotalJobs
    {
        get
        {
            return this.totalJobsField;
        }
        set
        {
            this.totalJobsField = value;
        }
    }
}
/// <remarks/>
[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.3038")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Xml.Serialization.XmlTypeAttribute(AnonymousType = true)]
public partial class WeeklyJobsDailyJobsJobsJob
{
    private string jobNameField;
    private string descriptionField;
    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute()]
    public string JobName
    {
        get
        {
            return this.jobNameField;
        }
        set
        {
            this.jobNameField = value;
        }
    }
    /// <remarks/>
    [System.Xml.Serialization.XmlAttributeAttribute()]
    public string Description
    {
        get
        {
            return this.descriptionField;
        }
        set
        {
            this.descriptionField = value;
        }
    }
}

之后，我将。cs文件添加到我的项目中，并创建了一个简单的winform，其中包含一个文本框，以便在我反序列化一些xml后显示一些数据。就像我说的，程序启动，文本框中没有显示任何内容，也没有抛出异常。这是我的winform:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    public string getExample()
    {
        XmlSerializer serializer = new XmlSerializer(typeof(WeeklyJobs));
        WeeklyJobs jobs;
        string xml = @"<?xml version = ""1.0""?>"
            + @"<WeeklyJobs>"
            + @"<DailyJobs Date = ""02/03/2012""/>"
            + @"<DailyJobs Date = ""02/04/2012"" TotalJobs = ""2"">"
            + @"<Jobs>"
            + @"<Job JobName = ""Job Name"" Description = ""Description""/>"
            + @"<Job JobName = ""Job Name"" Description = ""Description""/>"
            + @"</Jobs>"
            + @"</DailyJobs>"
            + @"</WeeklyJobs>";
        // Create an XmlTextReader
        using (XmlReader reader = XmlReader.Create(new StringReader(xml)))
        {
            jobs = (WeeklyJobs)serializer.Deserialize(reader);
        }
        return jobs.Items[0].Date;
    }
    private void Form1_Load(object sender, EventArgs e)
    {
        textBox1.Text = getExample();
    }

}

我有更简单的xml例子的工作，但我第二我试图添加一些复杂性到我的xml我失败了。我必须弄清楚如何使用这里的xml。谢谢你的帮助!谢谢大家!

Answer 1

好，第一个问题是XmlSerializer构造函数引发了一个未处理的异常，但不知何故它被忽略了。这解释了文本框为空的原因。我将调试器设置为在所有CLR异常时中断，并发现构造函数抛出InvalidOperationException——显然是在代码生成过程中:

无法生成临时类(result=1).

错误CS0030:不能转换类型"删除"。WeeklyJobsDailyJobsJobsJob[]' to '删除。WeeklyJobsDailyJobsJobsJob '

错误CS0029:不能隐式转换类型"DeleteMe"。WeeklyJobsDailyJobsJobsJob'到' delete '。WeeklyJobsDailyJobsJobsJob [] '

(构造函数也抛出了一个FileNotFound异常，但它也处理了这个异常，所以你可以忽略它。)

似乎问题是锯齿数组——你把一维数组改成锯齿数组了吗?当然，错误消息向我指出了这个方向，但我也从未在xsd生成的代码中见过锯齿数组，因此它看起来很可疑。我将两次出现的WeeklyJobsDailyJobsJobsJob[][]更改为WeeklyJobsDailyJobsJobsJob[]，应用程序运行正常。

作为题外话，您应该使用DateTime作为日期，但是XML序列化器不支持可变日期格式(参见https://stackoverflow.com/a/1118855/385844)。如果无法控制源，最好在将字符串存储到数据库或其他地方之前将其转换为日期。