c# - 未找到框架 ".NETFramework,Version=v4.7.1"的引用程序集

Question

我尝试在Linux(Ubuntu 18.10)下使用VSCode打开Unity3D项目。 omn​​isharp 扩展不会加载项目，并表示未找到程序集。

这可能看起来很愚蠢，但我还没有真正习惯.Net，而且我已经被这个错误困扰好几天了。我一直在尝试重新安装 dotnet(甚至使用 snap 包)、mono、vscode 和omnisharp 扩展。

欢迎任何帮助! :)

Unity版本:2018.3.1f1

日志:

dotnet -- 信息

.NET Core SDK (reflecting any global.json):
 Version:   2.2.103
 Commit:    8edbc2570a

Runtime Environment:
 OS Name:     ubuntu
 OS Version:  18.10
 OS Platform: Linux
 RID:         ubuntu.18.10-x64
 Base Path:   /usr/share/dotnet/sdk/2.2.103/

Host (useful for support):
  Version: 2.2.1
  Commit:  878dd11e62

.NET Core SDKs installed:
  2.2.103 [/usr/share/dotnet/sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.All 2.2.1 [/usr/share/dotnet/shared/Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.2.1 [/usr/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.2.1 [/usr/share/dotnet/shared/Microsoft.NETCore.App]

单声道版本

Mono JIT compiler version 4.6.2 (Debian 4.6.2.7+dfsg-1ubuntu1)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
    TLS:           __thread
    SIGSEGV:       altstack
    Notifications: epoll
    Architecture:  amd64
    Disabled:      none
    Misc:          softdebug 
    LLVM:          supported, not enabled.
    GC:            sgen

完整日志错误:

    Starting OmniSharp server at 1/26/2019, 7:13:55 PM
    Target: /home/eyap/Projects/Unity/TestProject/TestProject.sln

OmniSharp server started.
    Path: /home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/run
    PID: 30136

[info]: OmniSharp.Stdio.Host
        Starting OmniSharp on ubuntu 18.10 (x64)
[info]: OmniSharp.Services.DotNetCliService
        DotNetPath set to dotnet
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Located 1 MSBuild instance(s)
            1: StandAlone 15.0 - "/home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin"
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        MSBUILD_EXE_PATH environment variable set to '/home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin/MSBuild.dll'
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Registered MSBuild instance: StandAlone 15.0 - "/home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin"
            MSBuildExtensionsPath = /home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild
            BypassFrameworkInstallChecks = true
            CscToolPath = /home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin/Roslyn
            CscToolExe = csc.exe
            MSBuildToolsPath = /home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin
            TargetFrameworkRootPath = /usr/lib/mono/xbuild-frameworks
[info]: OmniSharp.Cake.CakeProjectSystem
        Detecting Cake files in '/home/eyap/Projects/Unity/TestProject'.
[info]: OmniSharp.Cake.CakeProjectSystem
        Could not find any Cake files
[info]: OmniSharp.WorkspaceInitializer
        Project system 'OmniSharp.DotNet.DotNetProjectSystem' is disabled in the configuration.
[info]: OmniSharp.MSBuild.ProjectSystem
        Detecting projects in '/home/eyap/Projects/Unity/TestProject/TestProject.sln'.
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/home/eyap/Projects/Unity/TestProject/Assembly-CSharp.csproj'
[info]: OmniSharp.Script.ScriptProjectSystem
        Detecting CSX files in '/home/eyap/Projects/Unity/TestProject'.
[info]: OmniSharp.Script.ScriptProjectSystem
        Could not find any CSX files
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpWorkspaceOptionsProvider
[info]: OmniSharp.WorkspaceInitializer
        Configuration finished.
[info]: OmniSharp.Stdio.Host
        Omnisharp server running using Stdio at location '/home/eyap/Projects/Unity/TestProject' on host 30056.
[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /home/eyap/Projects/Unity/TestProject/Assembly-CSharp.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for framework ".NETFramework,Version=v4.7.1" were not found. To resolve this, install the SDK or Targeting Pack for this framework version or retarget your application to a version of the framework for which you have the SDK or Targeting Pack installed. Note that assemblies will be resolved from the Global Assembly Cache (GAC) and will be used in place of reference assemblies. Therefore your assembly may not be correctly targeted for the framework you intend.
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/home/eyap/Projects/Unity/TestProject/Assembly-CSharp.csproj'.
/home/eyap/Projects/Unity/TestProject/Assembly-CSharp.csproj
/home/eyap/.vscode/extensions/ms-vscode.csharp-1.17.1/.omnisharp/1.32.8/omnisharp/msbuild/15.0/Bin/Microsoft.Common.CurrentVersion.targets(1195,5): Error: The reference assemblies for framework ".NETFramework,Version=v4.7.1" were not found. To resolve this, install the SDK or Targeting Pack for this framework version or retarget your application to a version of the framework for which you have the SDK or Targeting Pack installed. Note that assemblies will be resolved from the Global Assembly Cache (GAC) and will be used in place of reference assemblies. Therefore your assembly may not be correctly targeted for the framework you intend.

[fail]: OmniSharp.MSBuild.ProjectManager
        Attemped to update project that is not loaded: /home/eyap/Projects/Unity/TestProject/Assembly-CSharp.csproj

Answer 1

尝试了此处提到的步骤，但未能解决该错误。必须将 omnisharp.useGlobalMono 选项更改为 always。这适用于 VS Code=1.23.2 的 C# 扩展。

来源:Reddit Post

Your error output tells me that you're using the official C# extensionfor VS Code. The latest version of said extension, 1.23.2, has this tosay in its changelog:

For Mono-based development (e.g. Unity) that requires full .NET framework, you need to set "omnisharp.useGlobalMono": "always". This

is needed until Mono upgrades their bundled MSBuild version

The default setting, auto, does not work. Switch it to always andrestart the extension. Alternatively you could downgrade to 1.23.1.