我upgraded我的独立PCL库使用.Net Standard 2.0。现在，我尝试在Mac上构建，但出现以下错误：
XamlC:
Compiling Xaml, assembly: obj/Release/netstandard2.0/MyLibrary.dll
"obj/Release/netstandard2.0/XamlC.stamp" wird erstellt, da "AlwaysCreate" angegeben wurde.
GenerateSatelliteAssemblies:
Das Verzeichnis "obj/Release/netstandard2.0/de" wird erstellt.
/Library/Frameworks/Mono.framework/Versions/5.18.0/lib/mono/4.5/al.exe /culture:de /out:obj/Release/netstandard2.0/de/MyLibrary.resources.dll /template:obj/Release/netstandard2.0/MyLibrary.dll /embed:obj/Release/netstandard2.0/MyLibrary.Common.Localization.LibResources.de.resources
/usr/local/share/dotnet/sdk/2.1.700/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(129,5): error MSB4018: Unerwarteter Fehler bei der GenerateDepsFile-Aufgabe. [/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj]
/usr/local/share/dotnet/sdk/2.1.700/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(129,5): error MSB4018: System.TypeLoadException: Could not load type of field 'Microsoft.NET.Build.Tasks.DependencyContextBuilder:_filteredPackages' (12) due to: Could not resolve type with token 01000025 from typeref (expected class 'NuGet.Packaging.Core.PackageIdentity' in assembly 'NuGet.Packaging, Version=5.1.0.5, Culture=neutral, PublicKeyToken=31bf3856ad364e35') assembly:NuGet.Packaging, Version=5.1.0.5, Culture=neutral, PublicKeyToken=31bf3856ad364e35 type:NuGet.Packaging.Core.PackageIdentity member:(null) [/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj]
/usr/local/share/dotnet/sdk/2.1.700/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(129,5): error MSB4018: at Microsoft.NET.Build.Tasks.TaskBase.Execute () [0x00000] in <a7945d89c0ac41f8a1c76203a2991e34>:0 [/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj]
/usr/local/share/dotnet/sdk/2.1.700/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(129,5): error MSB4018: at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute () [0x00029] in <4e0a1f1d78cf4c1ebd6f9a3dbcebf3bb>:0 [/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj]
/usr/local/share/dotnet/sdk/2.1.700/Sdks/Microsoft.NET.Sdk/targets/Microsoft.NET.Sdk.targets(129,5): error MSB4018: at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask (Microsoft.Build.BackEnd.ITaskExecutionHost taskExecutionHost, Microsoft.Build.BackEnd.Logging.TaskLoggingContext taskLoggingContext, Microsoft.Build.BackEnd.TaskHost taskHost, Microsoft.Build.BackEnd.ItemBucket bucket, Microsoft.Build.BackEnd.TaskExecutionMode howToExecuteTask) [0x00212] in <4e0a1f1d78cf4c1ebd6f9a3dbcebf3bb>:0 [/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj]
Die Erstellung des Projekts "/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary/MyLibrary.csproj" ist abgeschlossen (Standardziele) -- FEHLER.
Die Erstellung des Projekts "/Users/someuser/.jenkins/workspace/MyLibrary/MyLibrary.sln" ist abgeschlossen, Build Ziel(e) -- FEHLER.
Fehler beim Buildvorgang.
您可以看到我正在使用Jenkins进行构建，但这根本不是问题（使用了msbuild）。这个问题似乎是known issue，但我不知道如何在给定的情况下（使用Visual Studio for Mac的旧版本）解决该问题。这些是使用的版本：
=== Visual Studio Community 2017 for Mac ===
Version 7.8.4 (build 1)
Installation UUID: 3d97ef3f-5e3c-496d-bba3-bf410eac83a0
GTK+ 2.24.23 (Raleigh theme)
Xamarin.Mac 5.0.0.0 ( / b40230c0)
Package version: 518000268
=== Mono Framework MDK ===
Runtime:
Mono 5.18.0.268 (2018-08/68aad3b0eb7) (64-bit)
Package version: 518000268
=== NuGet ===
Version: 4.8.2.5835
=== .NET Core ===
Runtime: /usr/local/share/dotnet/dotnet
Runtime Versions:
2.1.11
2.1.9
2.1.2
2.1.1
2.0.5
2.0.0
SDK: /usr/local/share/dotnet/sdk/2.1.700/Sdks
SDK Versions:
2.1.700
2.1.505
2.1.302
2.1.301
2.1.4
2.0.0
MSBuild SDKs: /Library/Frameworks/Mono.framework/Versions/5.18.0/lib/mono/msbuild/15.0/bin/Sdks
=== Xamarin.Profiler ===
Version: 1.6.10
Location: /Applications/Xamarin Profiler.app/Contents/MacOS/Xamarin Profiler
=== Updater ===
Version: 11
=== Xamarin.Android ===
Version: 9.3.0.23 (Visual Studio Community)
Android SDK: /Users/someuser/Library/Android/sdk
Supported Android versions:
4.4 (API level 19)
4.4.87 (API level 20)
5.0 (API level 21)
5.1 (API level 22)
6.0 (API level 23)
7.0 (API level 24)
7.1 (API level 25)
8.0 (API level 26)
8.1 (API level 27)
SDK Tools Version: 26.1.1
SDK Platform Tools Version: 27.0.1
SDK Build Tools Version: 27.0.1
=== Microsoft Mobile OpenJDK ===
Java SDK: /Users/someuser/Library/Developer/Xamarin/jdk/microsoft_dist_openjdk_8.0.25
1.8.0-25
Android Designer EPL code available here:
https://github.com/xamarin/AndroidDesigner.EPL
=== Android Device Manager ===
Version: 7.8.1.0
Hash: 8924ea4a
=== Apple Developer Tools ===
Xcode 10.2.1 (14490.122)
Build 10E1001
=== Xamarin.Mac ===
Version: 5.10.0.157 (Visual Studio Community)
Hash: 6bd94753
Branch: d16-1
Build date: 2019-06-12 17:28:48-0400
=== Xamarin.iOS ===
Version: 12.4.0.64 (Visual Studio Community)
Hash: 9c8d8e0a
Branch: xcode10.2
Build date: 2019-03-27 06:24:31-0400
=== Xamarin Inspector ===
Version: 1.4.3
Hash: db27525
Branch: 1.4-release
Build date: Mon, 09 Jul 2018 21:20:18 GMT
Client compatibility: 1
=== Build Information ===
Release ID: 708040001
Git revision: 9e1629d19c3f9f6d11a5d9895993a8edf1e7a3aa
Build date: 2019-05-10 19:37:45+00
Build branch: release-7.8
Xamarin extensions: c3cb4059acaf9142b2a5c176866edfc4c32b7da2
=== Operating System ===
Mac OS X 10.14.6
Darwin 18.7.0 Darwin Kernel Version 18.7.0
Thu Jun 20 18:42:21 PDT 2019
root:xnu-4903.270.47~4/RELEASE_X86_64 x86_64
我应该采取什么步骤来使构建再次工作？除了更新为Visual Studio 2019 for Mac（v。8+）以外？升级到更新的Mono版本是否足够（哪个版本？）？我的设置仍然可以使用吗？
现在我已经能够解决问题。多亏了post from AndreyAkinshin，我已将其修复。
使用dotnet --list-sdks，我得到了2.1.700作为最新版本。引用source：
[如果您使用mono 5.x，并且想要继续使用它，则需要更改.NET Core SDK版本。建议使用.NET Core SDK 2.1.5xx或2.2.1xx（例如2.1.505或2.2.108）。
我只需要uninstall .NET Core 2.1.700与
sudo rm -rf /usr/local/share/dotnet/sdk/2.1.700
[之后，我检查了dotnet --version，我正在使用的是哪个版本，它是2.1.505。如here所述，也可以使用其他一些选项。