Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.AspNetCore.Hosting, Version=1.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.
   at Sample1.Web.Program.Main(String[] args)

{
  "dependencies": {
    "Sample1.DataLayer": "1.0.0-*",
    "Sample1.PrsLayer.SysB.UserMg": "1.0.0-*",
    "Sample1.PrsLayer.SysBase": "1.0.0-*",
    "Sample1.PrsLayer.SysS.Setting": "1.0.0-*",
    "Sample1.SrvLayer.SysB.UserMg": "1.0.0-*",
    "Sample1.SrvLayer.SysBase": "1.0.0-*",
    "Sample1.SrvLayer.SysS.Setting": "1.0.0-*",
    "CoreCompat.System.Drawing": "1.0.0-beta006",
    "Sample1.ExternalResources": "1.0.0-*",
    "Sample1.SrvLayer.SysA.BookMg": "1.0.0-*",
    "Sample1.SrvLayer.UploadService": "1.0.0-*",
    "Sample1.PrsLayer.SysA.BookMg": "1.0.0-*",
    "Sample1.IocConfig": "1.0.0-*",
    "Sample1.MapperConfig": "1.0.0-*",
    "Sample1.PrsLayer.SysU.UiMg": "1.0.0-*",
    "Sample1.SrvLayer.SysU.UiMg": "1.0.0-*",
    "Sample1.PrsLayer.SysI.SubscribeNewsletter": "1.0.0-*",
    "Sample1.SrvLayer.SysI.SubscribeNewsletter": "1.0.0-*",
    "Wangkanai.Detection": "1.0.0-*",
    "Wangkanai.Detection.Abstractions": "1.0.0-*",
    "Wangkanai.Detection.Device": "1.0.0-*",
    "Wangkanai.Detection.Engine": "1.0.0-*",
    "Wangkanai.Detection.Platform": "1.0.0-*",
    "Wangkanai.Detection.Browser": "1.0.0-*",
    "StructureMap.Microsoft.DependencyInjection": "1.2.0",
    "CacheManager.Core": "0.9.1",
    "CacheManager.Microsoft.Extensions.Caching.Memory": "0.9.1",
    "CacheManager.Serialization.Json": "0.9.1",
    "Newtonsoft.Json": "9.0.2-beta1",
    "Microsoft.AspNetCore.SpaServices": "1.0.0-beta-000019",
    "AutoMapper": "5.1.1",
    "EFSecondLevelCache.Core": "1.0.1",
    "Microsoft.AspNetCore.Diagnostics.Elm": "0.2.0",
    "Microsoft.AspNetCore.Mvc": "1.1.0",
    "Microsoft.AspNetCore.Mvc.Localization": "1.1.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.1.0",
    "Microsoft.AspNetCore.Session": "1.1.0",
    "Microsoft.AspNetCore.StaticFiles": "1.1.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.1.0",
    "Microsoft.Extensions.Configuration.Json": "1.1.0",
    "Microsoft.Extensions.FileProviders.Embedded": "1.1.0",
    "Microsoft.Extensions.Logging.Console": "1.1.0",
    "Microsoft.Extensions.Logging.Debug": "1.1.0",
    "Microsoft.Net.Http.Headers": "1.1.0",
    "Microsoft.VisualStudio.Web.BrowserLink.Loader": "14.1.0",
    "System.Globalization": "4.3.0",
    "System.IO": "4.3.0",
    "System.Linq": "4.3.0",
    "System.Reflection": "4.3.0",
    "System.Runtime": "4.3.0",
    "System.Runtime.Extensions": "4.3.0",
    "System.Runtime.WindowsRuntime": "4.3.0",
    "System.Text.RegularExpressions": "4.3.0",
    "System.Threading.Tasks": "4.3.0",
    "Microsoft.VisualStudio.Web.CodeGenerators.Mvc": {
      "version": "1.1.0-preview4-final",
      "type": "build"
    },
    "Elmah.Io.AspNetCore": "1.0.1-pre-24",
    "Elmah.Io.Extensions.Logging": "1.0.17-pre",
    "Microsoft.VisualStudio.Web.CodeGeneration.Tools": {
      "version": "1.1.0-preview4-final",
      "type": "build"
    }
  },
  "tools": {
    "Microsoft.EntityFrameworkCore.Tools.DotNet": {
      "version": "1.1.0-preview4-final",
      "imports": [
        "portable-net45+win8"
      ]
    },
    "Microsoft.Extensions.SecretManager.Tools": "1.1.0-preview4-final",
    "Microsoft.VisualStudio.Web.CodeGeneration.Tools": {
      "version": "1.1.0-preview4-final",
      "imports": [
        "portable-net45+win8"
      ]
    },
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.1.0-preview4-final"
  },
  "frameworks": {
    "netcoreapp1.1": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.1.0"
        }
      },
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },
  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true,
    "embed": "Views/**/*.cshtml,Areas/**/Views/**/*.cshtml",
    "define": [ "DEBUG" ]
  },
  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },
  "publishOptions": {
    "include": [
      "wwwroot",
      "Views",
      "Areas/**/Views",
      "appsettings.json",
      "web.config"
    ]
  },
  "configurations": {
    "Release": {
      "buildOptions": {
        "optimize": true,
        "platform": "anycpu"
      }
    }
  },
  "scripts": {
    "precompile": [
      //"dotnet bundle"
    ],
    "prepublish": [
      //"bower install"
    ],
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

This Visual Studio Extension converts a WPF application built with the .NET Framework to a .NET Core 3 application. 

In part 1 Tim provides an overview of extensions and talks about some of the enhancements in Visual Studio 2015 for writing extensions. He creates a very simple extension and then gives a quick overview of an extension he is writing.