wcf - WCF:配置已知类型

Question

我想知道如何在WCF中配置已知类型。例如，我有一个人员类和一个雇员类。 员工类是人员类的子集。这两个类都标记有[DataContract]属性。

我不想硬编码类的已知类型，例如将[ServiceKnownType(typeof(Employee))]放在Person类上，以便WCF知道Employee是Person的子类。

现在，我将以下XML配置添加到主机的App.config中:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.runtime.serialization>
    <dataContractSerializer>
      <declaredTypes>
        <add type="Person, WCFWithNoLibrary, Version=1.0.0.0,Culture=neutral,PublicKeyToken=null">
          <knownType type="Employee, WCFWithNoLibrary, Version=1.0.0.0,Culture=neutral, PublicKeyToken=null" />
        </add>
      </declaredTypes>
    </dataContractSerializer>
  </system.runtime.serialization>
  <system.serviceModel>
    ....... 
  </system.serviceModel>
</configuration>

我编译了它，运行主机，在客户端添加了服务引用，并添加了一些代码并运行客户端。但是发生了一个错误:

The formatter threw an exception while trying to deserialize the message: There was an error while trying to deserialize parameter http://www.herbertsabanal.net:person. The InnerException message was 'Error in line 1 position 247. Element 'http://www.herbertsabanal.net:person' contains data of the 'http://www.herbertsabanal.net/Data:Employee' data contract. The deserializer has no knowledge of any type that maps to this contract. Add the type corresponding to 'Employee' to the list of known types - for example, by using the KnownTypeAttribute attribute or by adding it to the list of known types passed to DataContractSerializer.'. Please see InnerException for more details.

以下是数据契约(Contract):

[DataContract(Namespace="http://www.herbertsabanal.net/Data", Name="Person")]
    class Person
    {
        string _name;
        int _age;

        [DataMember(Name="Name", Order=0)]
        public string Name
        {
            get { return _name; }
            set { _name = value; }
        }

        [DataMember(Name="Age", Order=1)]
        public int Age
        {
            get { return _age; }
            set { _age = value; }
        }
    }


[DataContract(Namespace="http://www.herbertsabanal.net/Data", Name="Employee")]
    class Employee : Person
    {
        string _id;

        [DataMember]
        public string ID
        {
            get { return _id; }
            set { _id = value; }
        }
    }

顺便说一句，我没有为服务使用类库(WCF类库或非WCF类库)。我只是在宿主项目中对其进行了普通编码。

我猜配置文件一定有问题(请参见上面的配置文件)。否则我一定会丢失一些东西。任何帮助将不胜感激。

Answer 1

我想我已经找到答案了。

我上面发布的配置文件如下所示:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.runtime.serialization>
    <dataContractSerializer>
      <declaredTypes>
        <add type="Person, WCFWithNoLibrary, Version=1.0.0.0,Culture=neutral,PublicKeyToken=null">
          <knownType type="Employee, WCFWithNoLibrary, Version=1.0.0.0,Culture=neutral, PublicKeyToken=null" />
        </add>
      </declaredTypes>
    </dataContractSerializer>
  </system.runtime.serialization>
  <system.serviceModel>
    ....... 
  </system.serviceModel>
</configuration>

我刚刚添加的是 人员类的命名空间和 员工类的命名空间。并且不需要更长的版本和区域性值。...正确的配置应为:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <system.runtime.serialization>
    <dataContractSerializer>
      <declaredTypes>
        <add type="WCFWithNoLibrary.Person, WCFWithNoLibrary">
          <knownType type="WCFWithNoLibrary.Employee, WCFWithNoLibrary" />
        </add>
      </declaredTypes>
    </dataContractSerializer>
  </system.runtime.serialization>
  <system.serviceModel>
    ....... 
  </system.serviceModel>
</configuration>

现在它更短，更有意义。但是，如果使用了第三方库，则需要添加版本，文化和公钥 token 。