C# XML序列化不在XML中添加元素

我有一个从XSD生成的c类，我正在序列化它，我有一个场景，在特定条件下添加一些元素，这是我的类

[System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "4.0.30319.1")]
[System.SerializableAttribute()]
[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
public partial class MyRequestClass
{
    private string testNOField;
    private string mOBNOField;
    private int sTYPEField;
    private System.DateTime fRMDATEField;
    private System.DateTime tODATEField;
    public string TESTNO
    {
        get
        {
            return this.testNOField;
        }
        set
        {
            this.testNOField = value;
        }
    }

    public string MOBNO
    {
        get
        {
            return this.mOBNOField;
        }
        set
        {
            this.mOBNOField = value;
        }
    }


    public int STYPE
    {
        get
        {
            return this.sTYPEField;
        }
        set
        {
            this.sTYPEField = value;
        }
    }


    [System.Xml.Serialization.XmlElementAttribute(DataType = "date")]
    public System.DateTime FROMDATE
    {
        get
        {
            return this.fRMDATEField;
        }
        set
        {
            this.fRMDATEField = value;
        }
    }


    [System.Xml.Serialization.XmlElementAttribute(DataType = "date")]
    public System.DateTime TODATE
    {
        get
        {
            return this.tODATEField;
        }
        set
        {
            this.tODATEField = value;
        }
    }

}

FromDate和ToDate属性将在特定条件下添加，问题是当我为这两个属性提供值时，它没有在XML中添加这些属性，也没有出现错误，尽管在本例中添加了其他元素。 这就是我连载的方式

       string output = string.Empty;
        XmlSerializer xsSubmit = new XmlSerializer(typeof(MyRequestClass));
        using (StringWriter sww = new StringWriter())
            {
                using (XmlWriter writer = XmlWriter.Create(sww))
                {
                    //  sww.WriteLine(@"<?xml version=""1.0"" encoding=""UTF-8""?>");
                    xsSubmit.Serialize(writer , env);
                    output = sww.ToString();
                }
            }

        var doc = XDocument.Parse(output);
        Enumerable<XElement> emptyElements;
        emptyElements = from descendant in doc.Descendants()
                        where descendant.IsEmpty || string.IsNullOrWhiteSpace(descendant.Value)
                        select descendant;
        emptyElements.Remove();
        doc.Root.RemoveAttributes();
        output = doc.ToString();

---

其次，我在两种不同的情况下序列化这个类，一种情况下MOBNO应该出现在XML中，另一种情况下它不应该出现，我应该如何实现这个特性？

您可以动态添加/更改属性值，在这种情况下，隐藏元素将是XmlIgnore。代码如下：

 if (yourCondition)
 {
     XmlAttributes myRequestClassPropertyAttributes = new XmlAttributes();
     myRequestClassPropertyAttributes.XmlIgnore = true;

     XmlAttributeOverrides myRequestClassAttributes = new XmlAttributeOverrides();
     myRequestClassAttributes.Add(typeof(MyRequestClass), "MOBNO", myRequestClassPropertyAttributes);

     XmlSerializer xsSubmit = new XmlSerializer(typeof(MyRequestClass), myRequestClassAttributes);

     using (StringWriter sww = new StringWriter())
     {
          using (XmlWriter writer = XmlWriter.Create(sww))
          {
               //  sww.WriteLine(@"<?xml version=""1.0"" encoding=""UTF-8""?>");
               xsSubmit.Serialize(writer, env);
               output = sww.ToString();
          }
      }
}