我想在我的配置指定一个已知类型的,但我有问题,它从Object派生的事实。我可以使它发挥作用,通过指定属性中的已知类型。但在这种情况下,我需要使它从配置工作。
I'm trying to specify a known type in my config, but I'm having problems with the fact that it derives from Object. I can make it work specifying the known type via attribute. But in this case I need to make it work from the config.
下面是一个例子。以下工作正常:
Here's an example. The following works fine:
[ServiceContract]
[ServiceKnownType(typeof(MyData))]
public interface IContract
{
[OperationContract]
void Send(object data);
}
[DataContract]
public class MyData
{
[DataMember]
public string Message { get; set; }
}
但是,如果我删除ServiceKnownType属性,把在配置如下:
But if I remove the ServiceKnownType attribute and put the following in the config:
<system.runtime.serialization>
<dataContractSerializer>
<declaredTypes>
<add type="System.Object, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<knownType type="WpfApplication1.MyData, WpfApplication1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null"/>
</add>
</declaredTypes>
</dataContractSerializer>
</system.runtime.serialization>
我得到的消息ConfigurationErrorsException为属性'类型'的值是无效的错误是:该System.Object类型不能用作配置一个声明的类型
I get a ConfigurationErrorsException with the message "The value for the property 'type' is not valid. The error is: The type System.Object cannot be used as a declared type in config."
反正有使通过配置这项工作?
Is there anyway to make this work via config?
答案原来是它不可能做我想做的事情在配置文件中孤独。在配置上面对应于[KnownType]上DataContracts使用的属性。似乎有没有办法实施[ServiceKnownType]在config。
The answer turns out to be it's not possible to do what I want to do in the config file alone. The config above corresponds to the [KnownType] attribute used on DataContracts. There appears to be no way to implement [ServiceKnownType] in the config.
这是另一种方法是使用[ServiceKnownType(方法名,类型)]属性与自定义配置节。新的配置是这样的:
An alternate approach is to use [ServiceKnownType(methodName, type)] attribute with a custom configuration section. The new config looks like this:
<configuration>
<configSections>
<section
name="serviceKnownTypes"
type="WpfApplication1.ServiceKnownTypesSection, WpfApplication1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null"/>
</configSections>
<serviceKnownTypes>
<declaredServices>
<serviceContract type="WpfApplication1.IContract, WpfApplication1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null">
<knownTypes>
<knownType type="WpfApplication1.MyData, WpfApplication1, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null"/>
</knownTypes>
</serviceContract>
</declaredServices>
</serviceKnownTypes>
</configuration>
本合同:
[ServiceContract]
[ServiceKnownType("GetServiceKnownTypes", typeof(KnownTypeHelper))]
public interface IContract
{
[OperationContract]
void Send(object data);
}
[DataContract]
public class MyData
{
[DataMember]
public string Message { get; set; }
}
这包含返回已知类型的列表回调的辅助类
The helper class that contains the callback that returns the list of known types
public static class KnownTypeHelper
{
public static IEnumerable<Type> GetServiceKnownTypes(ICustomAttributeProvider provider)
{
List<Type> result = new List<Type>();
ServiceKnownTypesSection serviceKnownTypes = (ServiceKnownTypesSection)ConfigurationManager.GetSection("serviceKnownTypes");
DeclaredServiceElement service = serviceKnownTypes.Services[((Type)(provider)).AssemblyQualifiedName];
foreach (ServiceKnownTypeElement knownType in service.KnownTypes)
{
result.Add(knownType.Type);
}
return result;
}
}
在创建自定义配置部分的信息可以在这里找到:
Information on creating custom config sections can be found here:
http://msdn.microsoft.com/en-us/library/2tw134k3.aspx
http://msdn.microsoft.com/en-us/library/system.configuration.configurationcollectionattribute.aspx