更新 xamlx-workflow 服务引用引发 XamlObjectWriterException：“无法创建未知类型 [...]”答案

【问题标题】：Updating xamlx-workflow service reference threw XamlObjectWriterException : 'Cannot create unknown type [...]'更新 xamlx-workflow 服务引用引发 XamlObjectWriterException：“无法创建未知类型 [...]”
【发布时间】：2012-02-16 00:27:47
【问题描述】：

在 vs 2010 中，右键单击并更新指向我的 xamlx 工作流服务项目的服务引用时，它会引发错误（以原始 html 编写），说明：

XamlObjectWriterException : '无法创建未知类型 [...]'

[...] 指出我项目的一个消息变量。

我的工作流是由 WorkflowServiceHost 类托管的 xamlx。

这似乎是由于 SendResponse 消息。消息类型使用[DataContract] 和[DataMember]，并且在内容 UI 中选择了“参数”。

无法找出我的消息类型到底有什么问题。也许这是我的 wkf 项目的构建属性中的东西......

非常欢迎任何帮助。

这是发回的html：

There was an error downloading 'http://localhost:8008/WfDerogationCreation.xamlx'.
There was an error downloading 'http://localhost:8008/WfDerogationCreation.xamlx'.
The request failed with the error message:
--
<html>
    <head>
        <title>'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'.</title>
        <style>
         body {font-family:"Verdana";font-weight:normal;font-size: .7em;color:black;} 
         p {font-family:"Verdana";font-weight:normal;color:black;margin-top: -5px}
         b {font-family:"Verdana";font-weight:bold;color:black;margin-top: -5px}
         H1 { font-family:"Verdana";font-weight:normal;font-size:18pt;color:red }
         H2 { font-family:"Verdana";font-weight:normal;font-size:14pt;color:maroon }
         pre {font-family:"Lucida Console";font-size: .9em}
         .marker {font-weight: bold; color: black;text-decoration: none;}
         .version {color: gray;}
         .error {margin-bottom: 10px;}
         .expandable { text-decoration:underline; font-weight:bold; color:navy; cursor:hand; }
        </style>
    </head>
<body bgcolor="white">
            <span><H1>Server Error in '/' Application.<hr width=100% size=1 color=silver></H1>
            <h4> <i>'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'.</i> </h4></span>
            <font face="Arial, Helvetica, Geneva, SunSans-Regular, sans-serif ">
            <b> Description: </b>An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
            <br><br>
            <b> Exception Details: </b>System.Xaml.XamlObjectWriterException: 'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'.<br><br>
            <b>Source Error:</b> <br><br>
            <table width=100% bgcolor="#ffffcc">
               <tr>
                  <td>
                      <code>
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.</code>
                  </td>
               </tr>
            </table>
            <br>
            <b>Stack Trace:</b> <br><br>
            <table width=100% bgcolor="#ffffcc">
               <tr>
                  <td>
                      <code><pre>
[XamlObjectWriterException: 'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'.]
   System.Xaml.XamlObjectWriter.WriteStartObject(XamlType xamlType) +1131129
   System.Xaml.XamlWriter.WriteNode(XamlReader reader) +158
   System.Xaml.XamlServices.Transform(XamlReader xamlReader, XamlWriter xamlWriter, Boolean closeWriter) +106
   System.Xaml.XamlServices.Load(XamlReader xamlReader) +56
   System.ServiceModel.Activities.Activation.WorkflowServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) +302
   System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath) +1461
   System.ServiceModel.HostingManager.ActivateService(String normalizedVirtualPath) +44
   System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) +651

[ServiceActivationException: The service '/WfDerogationCreation.xamlx' cannot be activated due to an exception during compilation.  The exception message is: 'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'..]
   System.Runtime.AsyncResult.End(IAsyncResult result) +688590
   System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +190
   System.ServiceModel.Activation.HostedHttpRequestAsyncResult.ExecuteSynchronous(HttpApplication context, String routeServiceVirtualPath, Boolean flowContext, Boolean ensureWFService) +234
   System.ServiceModel.Activation.HttpModule.ProcessRequest(Object sender, EventArgs e) +379
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +148
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75
</pre></code>
                  </td>
               </tr>
            </table>
            <br>
            <hr width=100% size=1 color=silver>
            <b>Version Information:</b> Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.237
            </font>
    </body>
</html>
<!-- 
[XamlObjectWriterException]: 'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'.
   at System.Xaml.XamlObjectWriter.WriteStartObject(XamlType xamlType)
   at System.Xaml.XamlWriter.WriteNode(XamlReader reader)
   at System.Xaml.XamlServices.Transform(XamlReader xamlReader, XamlWriter xamlWriter, Boolean closeWriter)
   at System.Xaml.XamlServices.Load(XamlReader xamlReader)
   at System.ServiceModel.Activities.Activation.WorkflowServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(String normalizedVirtualPath)
   at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath)
[ServiceActivationException]: The service '/WfDerogationCreation.xamlx' cannot be activated due to an exception during compilation.  The exception message is: 'Cannot create unknown type '{http://schemas.microsoft.com/netfx/2009/xaml/activities}Variable({clr-namespace:CompanyName.WorkflowSecurity.Derogation.Messages;assembly=CompanyName.WorkflowSecurity}DerogRequest)'.' Line number '4' and line position '8'..
   at System.Runtime.AsyncResult.End[TAsyncResult](IAsyncResult result)
   at System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result)
   at System.ServiceModel.Activation.HostedHttpRequestAsyncResult.ExecuteSynchronous(HttpApplication context, String routeServiceVirtualPath, Boolean flowContext, Boolean ensureWFService)
   at System.ServiceModel.Activation.HttpModule.ProcessRequest(Object sender, EventArgs e)
   at System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
-->## Heading ##
--.
Metadata contains a reference that cannot be resolved: 'http://localhost:8008/WfDerogationCreation.xamlx'.
The server did not provide a meaningful reply; this might be caused by a contract mismatch, a premature session shutdown or an internal server error.
If the service is defined in the current solution, try building the solution and adding the service reference again.

【问题讨论】：

您需要使用Fusion log viewer. 进行调试，只需确保以管理员身份运行它，打开日志，然后在尝试调试之前重新启动。您将看到 CLR 在哪里寻找程序集，以及什么版本，并从那里确定为什么找不到它（如果您甚至安装了它）。

标签： wcf workflow-foundation-4

【解决方案1】：

我最终这样解决了这个问题：

在几个 ReceiveResponse / SendReply 活动中。

1/ 删除发送回复。 2/ 通过右键单击 ReceiveResponse 活动重新创建 SendReply 并重置已删除的属性。

Xamlx 服务参考然后上传得很好......

发现错误消息用原始 html 编写非常不合适，我的屏幕不够大，无法阅读所有内容。无论如何，谢谢你的帮助。

【讨论】：

【解决方案2】：

这是 Xaml 堆栈告诉您它不知道 CompanyName.WorkflowSecurity.Derogation.Messages 的方式。你需要做的是弄清楚为什么它不知道这个类型。

尽管“CompanyName.WorkflowSecurity}DerogRequest”注意到“}”，但程序集名称确实看起来很奇怪？是不是打错字了？

检查行号“4”和行位置“8”处的 XAMLX 文件

【讨论】：

嗨罗恩。实际上，我的 Xaml 中有问题的行只是对我的类型的引用，而不是对自身的类型实现的引用。 DerogRequest 是消息类型的名称，括号之间的部分是命名空间。但我最终找到了解决问题的方法。