C# 固定指定的框架'；Microsoft.AspNetCore.App'；，版本'；2.1.1'； Visual Studio 2017 15.8.1 新的空.NET核心MVC应用程序，通过新建项目向导生成Docker支持

运行应用程序后，我会收到以下错误：

The specified framework 'Microsoft.AspNetCore.App', version '2.1.1' was not found.
  - Check application dependencies and target a framework version installed at:
      /usr/share/dotnet/
  - Installing .NET Core prerequisites might help resolve this problem:
      http://go.microsoft.com/fwlink/?LinkID=798306&clcid=0x409
  - The .NET Core framework and SDK can be installed from:
      https://aka.ms/dotnet-download
  - The following versions are installed:
      2.1.0 at [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
The target process exited without raising a CoreCLR started event. Ensure that the target process is configured to use .NET Core. This may be expected if the target process did not run on .NET Core.

但是，我已检查并安装了以下设备：

C:\Users\homer>dotnet --list-sdks
1.0.0-preview2-003121 [C:\Program Files\dotnet\sdk]
1.0.0-preview2-003131 [C:\Program Files\dotnet\sdk]
1.0.3 [C:\Program Files\dotnet\sdk]
1.0.4 [C:\Program Files\dotnet\sdk]
1.1.0 [C:\Program Files\dotnet\sdk]
2.0.2 [C:\Program Files\dotnet\sdk]
2.0.3 [C:\Program Files\dotnet\sdk]
2.1.2 [C:\Program Files\dotnet\sdk]
2.1.4 [C:\Program Files\dotnet\sdk]
2.1.100 [C:\Program Files\dotnet\sdk]
2.1.101 [C:\Program Files\dotnet\sdk]
2.1.103 [C:\Program Files\dotnet\sdk]
2.1.104 [C:\Program Files\dotnet\sdk]
2.1.201 [C:\Program Files\dotnet\sdk]
2.1.202 [C:\Program Files\dotnet\sdk]
2.1.300 [C:\Program Files\dotnet\sdk]
2.1.301 [C:\Program Files\dotnet\sdk]
2.1.400 [C:\Program Files\dotnet\sdk]

C:\Users\homer>dotnet --list-runtimes
Microsoft.AspNetCore.All 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 1.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.1.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]

据我所知，它已经安装好了。显然，我的未更改的项目文件中某处有错误

Dockerfile

FROM microsoft/dotnet:2.1-aspnetcore-runtime AS base
WORKDIR /app
EXPOSE 19354
EXPOSE 44350

FROM microsoft/dotnet:2.1-sdk AS build
WORKDIR /src
COPY ["WebApplication4/WebApplication4.csproj", "WebApplication4/"]
RUN dotnet restore "WebApplication4/WebApplication4.csproj"
COPY . .
WORKDIR "/src/WebApplication4"
RUN dotnet build "WebApplication4.csproj" -c Release -o /app

FROM build AS publish
RUN dotnet publish "WebApplication4.csproj" -c Release -o /app

FROM base AS final
WORKDIR /app
COPY --from=publish /app .
ENTRYPOINT ["dotnet", "WebApplication4.dll"]

cproj

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp2.1</TargetFramework>
    <DockerTargetOS>Linux</DockerTargetOS>
    <UserSecretsId>9476cca2-b6a8-4c0e-a766-a2e480ded46a</UserSecretsId>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" Version="1.0.1916590" />
    <PackageReference Include="Newtonsoft.Json" Version="11.0.2" />
  </ItemGroup>

</Project>

netcoreapp2.1
Linux
9476cca2-b6a8-4c0e-a766-a2e480ded46a

---

那么，我在这里错过了什么来实现这一点呢？

我也遇到了同样的问题，只是将版本更改为2.0。不完全是解决您的问题，但可能会让您运行该项目

为此，请卸载项目，然后编辑项目文件并更改

---

netcoreapp2.1到netcoreapp2.0将Dockerfile修改为（注意2.1.1而不是2.1）修复了以下问题：

FROM microsoft/dotnet:2.1.1-aspnetcore-runtime AS base
WORKDIR /app
EXPOSE 19354
EXPOSE 44350

FROM microsoft/dotnet:2.1.1-sdk AS build
WORKDIR /src
COPY ["WebApplication4/WebApplication4.csproj", "WebApplication4/"]
RUN dotnet restore "WebApplication4/WebApplication4.csproj"
COPY . .
WORKDIR "/src/WebApplication4"
RUN dotnet build "WebApplication4.csproj" -c Release -o /app

FROM build AS publish
RUN dotnet publish "WebApplication4.csproj" -c Release -o /app

FROM base AS final
WORKDIR /app
COPY --from=publish /app .
ENTRYPOINT ["dotnet", "WebApplication4.dll"]

如果M$实际查看了您机器上安装的内容并生成正确的文件，这不是很好吗？：-）