.net 访问服务器变量时发生异常

我已经创建了一个RESTful WCF 4.0服务。为了捕获并记录未处理的异常，我创建了一个错误处理程序，我想在其中收集服务器变量以用于记录。但是，访问HttpContext.Current.Request.ServerVariables会引发“值不在预期范围内”异常：

public class MyErrorHandler : IErrorHandler, IServiceBehavior
{
    public void AddBindingParameters(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase, System.Collections.ObjectModel.Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters)
    {
    }

    public void ApplyDispatchBehavior(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase)
    {
        IErrorHandler errorHandler = new VirusInfoErrorHandler();

        foreach (ChannelDispatcherBase channelDispatcherBase in serviceHostBase.ChannelDispatchers)
        {
            ChannelDispatcher channelDispatcher = channelDispatcherBase as ChannelDispatcher;

            if (channelDispatcher != null)
            {
                channelDispatcher.ErrorHandlers.Add(errorHandler);
            }
        }
    }

    public void Validate(ServiceDescription serviceDescription, System.ServiceModel.ServiceHostBase serviceHostBase)
    {
    }

    public bool HandleError(Exception error)
    {
        // I'd like to log here but accessing
        // HttpContext.Current.Request.ServerVariables
        // throws a "Value does not fall within the expected range" exception.

        return true;
    }

    public void ProvideFault(Exception error, MessageVersion version, ref Message fault)
    {
    }
}

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没有办法从WCF的上下文中检索服务器变量吗？

您的服务类是否标记了以下属性

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Required)]

---

为什么要检索这些“变量”？它们在任何情况下都不存在。相反，看看你能从各种上下文对象中得到什么。当你说“它们在任何情况下都不存在”时，你能解释一下吗？我关心的是检索请求者的IP地址和服务器的名称。从WebOperationContext可以这样做吗？我看不到来自IErrorHander的方法。“服务器变量”是web服务器发明的一种虚构，它使脚本语言更容易访问这些信息。在某个地方实际上没有一组变量。简要研究表明，您可以从

providdefault

中访问

OperationContext

。

    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Required)]
[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerCall, ConcurrencyMode = ConcurrencyMode.Multiple)]
public class MyService
{
    [WebGet(UriTemplate="/my-method", ResponseFormat=WebMessageFormat.Json)]
    public Message MyMethod()
    {
        // might return good things
        // might throw an exception in downstream tiers
    }
}

[AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Required)]