我有一些非常简单的代码。
//File Company.cs
using System;
using Sharpen;
using System.Reflection;
using System.Runtime.Serialization;
namespace XPathTest
{
[DataContract(IsReference=true)]
public class Company
{
[DataMember]
public AList<Person> employees {get; set;}
public Company ()
{
employees = new AList<Person>();
}
}
}
//File Employee.cs
using System;
using System.Reflection;
using System.Runtime.Serialization;
namespace XPathTest
{
[DataContract(IsReference=true)]
public class Employee : Person
{
public Employee ()
{
}
}
}
//File Manager.cs
using System;
using Sharpen;
using System.Reflection;
using System.Runtime.Serialization;
namespace XPathTest
{
[DataContract(IsReference=true)]
public class Manager : Person
{
[DataMember(EmitDefaultValue=false)]
public AList<Person> employees { get; set; }
public Manager ()
{
employees = new AList<Person>();
}
public void AddEmployee(Person employee)
{
employees.Add (employee);
}
}
}
//File Person.cs
using System;
using System.Reflection;
using System.Runtime.Serialization;
namespace XPathTest
{
[DataContract(IsReference=true)]
public class Person
{
[DataMember]
public int SSNum { get; set; }
[DataMember]
public string name { get; set; }
[DataMember(EmitDefaultValue=false)]
public Person manager {get; set;}
public Person ()
{
}
public void SetManager(Person manager)
{
this.manager = manager;
}
}
}
//File Main.cs
using System;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.XPath;
using System.IO;
using System.Reflection;
using System.Runtime.Serialization;
using XPathTest;
public class Test
{
public static void Main()
{
// Read and write purchase orders.
Test t = new Test();
t.MarshalCompany ("po.xml");
}
public Company BuildCompany ()
{
Company company = new Company();
Manager employee1 = new Manager();
employee1.SSNum = 1337;
employee1.name ="Jane Doe";
company.employees.Add(employee1);
Employee employee2 = new Employee();
employee2.SSNum = 8008132;
employee2.name = "John Smith";
employee2.SetManager(employee1);
company.employees.Add(employee2);
Employee employee3 = new Employee();
employee3.SSNum = 1138;
employee3.name = "Anne Jones";
employee3.SetManager(employee1);
company.employees.Add(employee3);
employee1.AddEmployee(employee2);
employee1.AddEmployee(employee3);
Manager manager1 = new Manager();
manager1.SSNum = 314;
manager1.name = "Boss Hog";
//manager1.setManager(manager1);
manager1.AddEmployee(employee1);
company.employees.Add(manager1);
return company;
}
public void MarshalCompany(string filename)
{
Company po = BuildCompany ();
System.Runtime.Serialization.DataContractSerializer serializer = new DataContractSerializer (po.GetType ());
using (FileStream stream = File.Create (filename))
{
serializer.WriteObject(stream, po);
}
}
我碰巧得到了这个输出......
<Company xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:z="http://schemas.microsoft.com/2003/10/Serialization/" xmlns="http://schemas.datacontract.org/2004/07/XPathTest" z:Id="i1">
<employees>
<Person i:type="Manager" z:Id="i2">
<SSNum>1337</SSNum>
<manager i:nil="true"/>
<name>Jane Doe</name>
<employees>
<Person i:type="Employee" z:Id="i3">
<SSNum>8008132</SSNum>
<manager i:type="Manager" z:Ref="i2"/>
<name>John Smith</name>
</Person>
<Person i:type="Employee" z:Id="i4">
<SSNum>1138</SSNum>
<manager i:type="Manager" z:Ref="i2"/>
<name>Anne Jones</name>
</Person>
</employees>
</Person>
<Person i:type="Employee" z:Ref="i3"/>
<Person i:type="Employee" z:Ref="i4"/>
<Person i:type="Manager" z:Id="i5">
<SSNum>314</SSNum>
<manager i:nil="true"/>
<name>Boss Hog</name>
<employees>
<Person i:type="Manager" z:Ref="i2"/>
</employees>
</Person>
</employees>
</Company>
为什么 [DataMember(EmitDefaultValue=false)] 属性不起作用？
输出显示类似
<manager i:nil="true"/>
由于大小的原因，我不想要它，以及与 jaxb 输出的兼容性，即使某些东西是空的（无元素）。
我在 MSDN 甚至其他 stackoverflow 页面上读过的所有内容都说这应该有效，但事实并非如此。我将不胜感激任何可以帮助我弄清楚为什么 nil 元素仍然存在的人。对我来说，如果你有来自“ngit”项目的 Sharpen 命名空间（对于 Sharpen.AList，它只是 Collections.List 的包装器），那么发布的代码就是工作代码。我最近一直在做很多 java/c#。
我对此感兴趣的原因是因为我有大量的数据，这些数据基本上是一些用 Jaxb 2.2.7 序列化的 java 类，我通过 TCP 将它们发送到具有类似 java 类的 C# 客户端。目标是将这些数据直接解组到 c# 类中。不幸的是，我无法在 jaxb 中找到为每个序列化的对象自然创建通用引用跟踪器的方法，并且必须为我想要跟踪和引用的每个类手动编写一个 @XmlAdapter。DataContract 似乎很自然且很容易地做到了这一点。但是，JAXB 不会在输出 xml 中放置对 null 元素的引用，我想确保 DataContract 的东西模仿相同的行为。
谢谢你。