1、项目中调用代码
public IServiceProvider ConfigureServices(IServiceCollection services){ // Add services to the collection. services.AddMvc();}
抛出异常信息：
KeyNotFoundException: The given key was not present in the dictionary. System.Collections.Generic.Dictionary.get_Item(TKey key)
Microsoft.AspNetCore.Mvc.Internal.DefaultAssemblyPartDiscoveryProvider+CandidateResolver.ComputeClassification(string dependency)
Microsoft.AspNetCore.Mvc.Internal.DefaultAssemblyPartDiscoveryProvider+CandidateResolver.ComputeClassification(string dependency)
Microsoft.AspNetCore.Mvc.Internal.DefaultAssemblyPartDiscoveryProvider+CandidateResolver.ComputeClassification(string dependency)
Microsoft.AspNetCore.Mvc.Internal.DefaultAssemblyPartDiscoveryProvider+CandidateResolver.ComputeClassification(string dependency)
Microsoft.AspNetCore.Mvc.Internal.DefaultAssemblyPartDiscoveryProvider+CandidateResolver+d__4.MoveNext() System.Linq.Enumerable+d__17.MoveNext() System.Linq.Enumerable+WhereSelectEnumerableIterator.MoveNext() Microsoft.Extensions.DependencyInjection.MvcCoreServiceCollectionExtensions.GetApplicationPartManager(IServiceCollection services)
Microsoft.Extensions.DependencyInjection.MvcCoreServiceCollectionExtensions.AddMvcCore(IServiceCollection services)
Microsoft.Extensions.DependencyInjection.MvcServiceCollectionExtensions.AddMvc(IServiceCollection services) MyWebApiProject.Startup.ConfigureServices(IServiceCollection services) in Startup.cs System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
Microsoft.AspNetCore.Hosting.ConventionBasedStartup.ConfigureServices(IServiceCollection services) Microsoft.AspNetCore.Hosting.Internal.WebHost.EnsureApplicationServices() Microsoft.AspNetCore.Hosting.Internal.WebHost.BuildApplication()
csproj文件内容：
net461
2、解决方法
在添加MVC之前添加ApplicationPartManager
var manager = new ApplicationPartManager();
manager.ApplicationParts.Add(new AssemblyPart(typeof(Startup).Assembly));
services.AddSingleton(manager);
services.AddMvc();