使用新的 Xamarin 窗体生成时出现"XamlCTask"任务意外失败"错误

Question

更新到最新的Xamarin.Forms(2.3.4.224(后，我不断收到生成错误。 有人知道这可能是什么吗？

我怀疑这可能与他们通过有关附加属性的新版本引入的新行为更改有关(但我不知道这意味着(

更多信息请点击此处 https://forums.xamarin.com/discussion/92455/xamarin-forms-2-3-4-224

这是我的构建日志

Error       The "XamlCTask" task failed unexpectedly.
System.ArgumentException: An item with the same key has already been added.
Server stack trace: 
   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)
   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
   at Xamarin.Forms.Xaml.XamlParser.ParseXamlElementFor(IElementNode node, XmlReader reader)
   at Xamarin.Forms.Xaml.XamlParser.ReadNode(XmlReader reader, Boolean nested)
   at Xamarin.Forms.Xaml.XamlParser.ParseXamlElementFor(IElementNode node, XmlReader reader)
   at Xamarin.Forms.Xaml.XamlParser.ReadNode(XmlReader reader, Boolean nested)
   at Xamarin.Forms.Xaml.XamlParser.ParseXamlElementFor(IElementNode node, XmlReader reader)
   at Xamarin.Forms.Xaml.XamlParser.ReadNode(XmlReader reader, Boolean nested)
   at Xamarin.Forms.Xaml.XamlParser.ParseXamlElementFor(IElementNode node, XmlReader reader)
   at Xamarin.Forms.Xaml.XamlParser.ParseXaml(RootNode rootNode, XmlReader reader)
   at Xamarin.Forms.Build.Tasks.XamlTask.ParseXaml(Stream stream, TypeReference typeReference)
   at Xamarin.Forms.Build.Tasks.XamlCTask.Execute(IList`1& thrownExceptions)
   at Xamarin.Forms.Build.Tasks.XamlTask.Execute()
   at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
   at System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg)
Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at Microsoft.Build.Framework.ITask.Execute()
   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
   at Microsoft.Build.BackEnd.TaskBuilder.<ExecuteInstantiatedTask>d__26.MoveNext() Shared          

Answer 1

我不确定这是否是相同的情况，但我遇到了同样的问题。

我安装了不同版本的表单。在我更新了所有 nuget 包并删除了所有 obj 和 bin 文件夹后，我能够毫无错误地进行构建。

Answer 2

清理解决方案并关闭 Visual Studio 2017。当您再次打开它时，错误将消失。