我正在尝试在WCF服务中注入一些业务服务 . 我读到了这篇非常有意思的帖子:How do I pass values to the constructor on my wcf service?
我做了以下事情:
Custom ServiceHost
public class UnityServiceHost : ServiceHost
{
public UnityServiceHost(IUnityContainer container, Type serviceType, params Uri[] baseAddresses)
: base(serviceType, baseAddresses)
{
if (container == null)
{
throw new ArgumentNullException(nameof(container));
}
foreach (ContractDescription contractDescription in ImplementedContracts.Values)
{
contractDescription.Behaviors.Add(new UnityInstanceProvider(serviceType, container));
}
}
}
Custom Instance Provider
public class UnityInstanceProvider : IInstanceProvider, IContractBehavior
{
private readonly Type m_serviceType;
private readonly IUnityContainer m_container;
public UnityInstanceProvider(Type serviceType, IUnityContainer container)
{
m_serviceType = serviceType;
m_container = container;
}
public object GetInstance(InstanceContext instanceContext, Message message)
{
return GetInstance(instanceContext);
}
public object GetInstance(InstanceContext instanceContext)
{
return m_container.Resolve(m_serviceType);
}
public void ReleaseInstance(InstanceContext instanceContext, object instance)
{
(instance as IDisposable)?.Dispose();
}
public void AddBindingParameters(ContractDescription contractDescription, ServiceEndpoint endpoint, BindingParameterCollection bindingParameters) { }
public void ApplyClientBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, ClientRuntime clientRuntime) { }
public void ApplyDispatchBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, DispatchRuntime dispatchRuntime)
{
dispatchRuntime.InstanceProvider = this;
}
public void Validate(ContractDescription contractDescription, ServiceEndpoint endpoint) { }
}
我看起来像这样的服务行为:
[ServiceBehavior]
public class MyService : IMyService
{
public ServerInformationService(ISomeDependency coreManager)
{
//...
}
}
但是我没有进入 GetInstance
,当我运行代码时,我得到了这个:
提供的服务类型无法作为服务加载,因为它没有默认(无参数)构造函数 . 要解决此问题,请为该类型添加默认构造函数,或将该类型的实例传递给主机 .
我做错了什么?看起来我的实例提供程序甚至没有使用过
1 回答
我终于找到了解决方案 . 我将我的InstanceProvider应用于Contact而不是服务 .
这是我的最终(工作)解决方案:
行为实例提供者:
它是有效的,因为我是自托管服务(
new UnityServiceHost(...) ....
,如果是在IIS上,我无法创建这种行为