Нет преобразования между HelloWorldComponent и System.Func`2 [System.Collections.Generic.IDictionary`2 // Имя параметра: подпись
Я работаю над курсом Скотта Аллена MVC 5 Основы по Pluralsight
Я получаю сообщение об ошибке при использовании (WebApp.Start (uri)) в приведенном ниже коде.
Ошибка
An unhandled exception of type 'System.ArgumentException' occurred in Microsoft.Owin.dll
System.ArgumentException was unhandled
HResult=-2147024809
Message=No conversion available between ConsoleApplication1.HelloWorldComponent and System.Func`2[System.Collections.Generic.IDictionary`2[System.String,System.Object],System.Threading.Tasks.Task].
Parameter name: signature
Source=Microsoft.Owin
ParamName=signature
StackTrace:
at Microsoft.Owin.Builder.AppBuilder.Convert(Type signature, Object app)
at Microsoft.Owin.Builder.AppBuilder.BuildInternal(Type signature)
at Microsoft.Owin.Builder.AppBuilder.Build(Type returnType)
at Microsoft.Owin.Hosting.ServerFactory.ServerFactoryAdapter.Create(IAppBuilder builder)
at Microsoft.Owin.Hosting.Engine.HostingEngine.StartServer(StartContext context)
at Microsoft.Owin.Hosting.Engine.HostingEngine.Start(StartContext context)
at Microsoft.Owin.Hosting.Starter.DirectHostingStarter.Start(StartOptions options)
at Microsoft.Owin.Hosting.Starter.HostingStarter.Start(StartOptions options)
at Microsoft.Owin.Hosting.WebApp.StartImplementation(IServiceProvider services, StartOptions options)
at Microsoft.Owin.Hosting.WebApp.Start(StartOptions options)
at Microsoft.Owin.Hosting.WebApp.Start[TStartup](StartOptions options)
at Microsoft.Owin.Hosting.WebApp.Start[TStartup](String url)
at ConsoleApplication1.Program.Main(String[] args) in e:\EShared\Dev2015\WebAppScottAllen\ConsoleApplication1\ConsoleApplication1\Program.cs:line 16
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadSt,art()
InnerException:
Код
using System;
using System.Collections.Generic;
using System.IO;
using System.Threading.Tasks;
using Microsoft.Owin.Hosting;
using Owin;
namespace ConsoleApplication1
{
using AppFunc = Func<IDictionary<string, object>, Task>;
class Program
{
static void Main(string[] args)
{
string uri = "http://localhost:8080";
using (WebApp.Start<Startup>(uri)) // Katana Please start, using the configuration from the Startup class and listening on the port given by the uri
{
Console.WriteLine("Started!");
Console.ReadKey();
Console.WriteLine("Stopping!");
}
}
}
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.Use<HelloWorldComponent>();
}
}
public class HelloWorldComponent
{
AppFunc _next;
public HelloWorldComponent(AppFunc next)
{
_next = next;
}
// Katana uses reflection to find this Invoke function that matches the AppFunc signature
public Task Invoke(IDictionary<string, object> environment)
{
var response = environment["owin.ResponseBody"] as Stream;
using (var writer = new StreamWriter(response))
{
return writer.WriteAsync("Hello");
}
}
}
}
packages.config - это
<?xml version="1.0" encoding="utf-8"?>
<packages>
<package id="Microsoft.Owin" version="3.0.1" targetFramework="net451" />
<package id="Microsoft.Owin.Diagnostics" version="3.0.1" targetFramework="net451" />
<package id="Microsoft.Owin.Host.HttpListener" version="3.0.1" targetFramework="net451" />
<package id="Microsoft.Owin.Host.SystemWeb" version="3.0.1" targetFramework="net451" />
<package id="Microsoft.Owin.Hosting" version="3.0.1" targetFramework="net451" />
<package id="Owin" version="1.0" targetFramework="net451" />
</packages>
Интересно, не использовал, чтобы получить это сообщение, поэтому мне интересно, что могло измениться