Question

我下载了webapi的示例代码，我收到了此异常我使用Visual Studio 2012 Ultimate Version打开了这个示例，我安装了最新的newtonsoft版本。运行此应用程序时出现此错误。它编译成功。知道为什么会出现这个错误并且有办法解决这个异常。

System.MissingMethodException was unhandled by user code
  HResult=-2146233069
  Message=Method not found: 'Void Newtonsoft.Json.Serialization.DefaultContractResolver.set_IgnoreSerializableAttribute(Boolean)'.
  Source=System.Net.Http.Formatting
  StackTrace:
       at System.Net.Http.Formatting.JsonContractResolver..ctor(MediaTypeFormatter formatter)
       at System.Net.Http.Formatting.JsonMediaTypeFormatter..ctor()
       at System.Net.Http.Formatting.MediaTypeFormatterCollection.CreateDefaultFormatters()
       at System.Net.Http.Formatting.MediaTypeFormatterCollection..ctor()
       at System.Web.Http.HttpConfiguration.DefaultFormatters()
       at System.Web.Http.HttpConfiguration..ctor(HttpRouteCollection routes)
       at System.Web.Http.GlobalConfiguration.<.cctor>b__0()
       at System.Lazy`1.CreateValue()
       at System.Lazy`1.LazyInitValue()
       at System.Lazy`1.get_Value()
       at System.Web.Http.GlobalConfiguration.get_Configuration()
       at System.Web.Http.RouteCollectionExtensions.MapHttpRoute(RouteCollection routes, String name, String routeTemplate, Object defaults, Object constraints, HttpMessageHandler handler)
       at System.Web.Http.RouteCollectionExtensions.MapHttpRoute(RouteCollection routes, String name, String routeTemplate, Object defaults)
       at WebAPIRc.RouteConfig.RegisterRoutes(RouteCollection routes) in c:\Users\viemon\Downloads\WebAPIRc\WebAPIRc\WebAPIRc\App_Start\RouteConfig.cs:line 17
       at WebAPIRc.WebApiApplication.Application_Start() in c:\Users\viemon\Downloads\WebAPIRc\WebAPIRc\WebAPIRc\Global.asax.cs:line 36
  InnerException:

以下是失败的代码

public class RouteConfig
    {
        public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
          //Exception error start
            routes.MapHttpRoute(
                name: "DefaultApi",
                routeTemplate: "api/{controller}/{id}",
                defaults: new { id = RouteParameter.Optional }
            );
          //exception error end

            routes.MapRoute(
                name: "Default",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
            );
        }
    }

我知道我需要为NuGet from this post启用“Include prerelease”，但是如何打开如何打开NuGet的“Include Prerelease”？

Answer 1

如何打开如何打开NuGet的“Include Prerelease”？

要使用“Include Prerelease”安装Json.NET，请在the Package Manager Console

中运行以下命令

Install-Package Newtonsoft.Json –IncludePrerelease

Answer 2

另一个原因可能是您的GAC中有旧版本。对我来说，版本是在.NET 4.0 GAC中删除，这解决了问题

Answer 3

在我的情况下你我只是删除RouteConfig中的以下行（它已被删除）。

  //Exception error start
    routes.MapHttpRoute(
        name: "DefaultApi",
        routeTemplate: "api/{controller}/{id}",
        defaults: new { id = RouteParameter.Optional }
    );
  //exception error end

在VS2012中，这应该足够了。

        routes.MapRoute(
            name: "Default",
            url: "{controller}/{action}/{id}",
            defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
        );

您可能还需要验证控制器。如果您不确定它们的用途，请在RouteConfig中删除一些Class引用。在我的案例中，我只保留这两个：

using System.Web.Mvc;
using System.Web.Routing;

另一个解决方案是，如果您想要并有时间找出导致冲突的原因，那么您可以将项目构建输出详细程度设置为详细(Go to Tools-> Options -> Project and Solutions -> Build and Run -> MSBuild project build output verbosity) and upon build check your logs.

找不到方法'Void Newtonsoft.Json.Serialization.DefaultContractResolver.set_IgnoreSerializableAttribute（Boolean）

3 个答案: