现在 WebServiceHost2Factory 已死，如何从 WCF 休息服务返回错误文本？答案

【问题标题】：Now that WebServiceHost2Factory is dead, how do I return error text from a WCF rest service?现在 WebServiceHost2Factory 已死，如何从 WCF 休息服务返回错误文本？
【发布时间】：2013-03-12 19:16:55
【问题描述】：

我已经看到几个对 WebServiceHost2Factory 的引用，因为 class to use to effectively 处理 WCF Rest 服务中的错误。显然对于那个类，我只需要抛出一个 WebProtocolException 并且响应的主体将包含相关信息。

这个班级现在似乎已经失宠了。 .NET 4 堆栈中的某个地方有替代品吗？

我试图弄清楚如果出现问题，如何在对 POST 操作的响应正文中返回错误文本。关键问题在下面所有 * 的旁边

例子：

[Description("Performs a full enroll and activation of the member into the Loyalty program")]
[OperationContract]
[WebInvoke(Method = "POST", UriTemplate = "/fullenroll/{clientDeviceId}",
    BodyStyle = WebMessageBodyStyle.Bare,
    RequestFormat = WebMessageFormat.Json,
    ResponseFormat = WebMessageFormat.Json)]
public MemberInfo FullEnroll(string clientDeviceId, FullEnrollmentRequest request)
{
    Log.DebugFormat("FullEnroll. ClientDeviceId: {0}, Request:{1}", clientDeviceId, request);
    MemberInfo ret = null;
    try
    {
      //Do stuff
    }
    catch (FaultException<LoyaltyException> fex)
    {
        Log.ErrorFormat("[loyalty full enroll] Caught faultexception attempting to full enroll. Message: {0}, Reason: {1}, Data: {2}", fex.Message, fex.Reason, fex.Detail.ExceptionMessage);
        HandleException("FullEnroll", fex, fex.Detail.ExceptionMessage);
    }
    catch (Exception e)
    {
        Log.ErrorFormat(
            "[loyalty full enroll] Caught exception attempting to full enroll. Exception: {0}", e);
        HandleException("FullEnroll", e);
    }
    return ret;
}


/// <summary>
/// Deals w/ the response when Exceptions are thrown
/// </summary>
private static Exception HandleException(string function, Exception e, string statusMessage = null)
{
    // Set the return context, handle the error
    if (WebOperationContext.Current != null)
    {
        var response = WebOperationContext.Current.OutgoingResponse;

        // Set the error code based on the Exception
        var errorNum = 500;
        if (e is HttpException)
            errorNum = ((HttpException)e).ErrorCode;

        response.StatusCode = (HttpStatusCode) Enum.Parse(typeof (HttpStatusCode), errorNum.ToString());
        response.StatusDescription = statusMessage;
        // ****************************************************
        // How can I return this as the body of the Web Method?
        // ****************************************************
        WebOperationContext.Current.CreateTextResponse(statusMessage);
    }

    return (e is HttpException) ? e : new HttpException(500, string.Format("{0} caught an exception", function));
}

【问题讨论】：

标签： c# .net wcf rest

【解决方案1】：

This answer 似乎建议使用以下内容，

HttpContext.Current.Response.Write(statusMessage);

编辑 - 作为 cmets 中的 tobyb mentioned，AspNetCompatibility 是必需的。

开启方法如下：

<system.serviceModel>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true">
    <!--  ...  -->
</system.serviceModel>

【讨论】：

行得通！谢谢。唯一需要注意的是，该服务需要 AspNetCompatibility，这对我来说不是问题，但对其他人来说可能是问题。再次感谢！