vs2019 添加服务引用时发生错误

Question

Checking project for required NuGet packges...
Installing NuGet packages to project...
Installing package 'NSwag.ApiDescription.Client' with version '13.0.5'.
ErrorNuGet.PackageManagement.PackageReferenceRollbackException: Package restore failed. Rolling back package changes for 'xxx.Server'.
   at NuGet.PackageManagement.NuGetPackageManager.<ExecuteBuildIntegratedProjectActionsAsync>d__80.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
   at NuGet.PackageManagement.NuGetPackageManager.<ExecuteNuGetProjectActionsAsync>d__77.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.PackageManagement.NuGetPackageManager.<InstallPackageAsync>d__48.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.PackageManagement.NuGetPackageManager.<InstallPackageAsync>d__47.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.VisualStudio.VsPackageInstaller.<InstallInternalCoreAsync>d__30.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
   at NuGet.VisualStudio.VsPackageInstaller.<InstallInternalAsync>d__29.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at NuGet.VisualStudio.VsPackageInstaller.<InstallInternalAsync>d__29.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.VisualStudio.Threading.JoinableTask.CompleteOnCurrentThread()
   at NuGet.VisualStudio.VsPackageInstaller.RunJTFWithCorrectContext(Project project, Func`1 asyncTask)
   at NuGet.VisualStudio.VsPackageInstaller.InstallPackage(String source, Project project, String packageId, String version, Boolean ignoreDependencies)
   at Microsoft.WebTools.Shared.VS.NuGet.NuGetPackageManager.<InstallAsync>d__28.MoveNext()

Answer 1

这个错误信息看起来是在安装NuGet包时出现了问题。以下是一些可能的解决方法：

1. 清理NuGet缓存：尝试清理NuGet缓存并重新安装NuGet包。可以通过在Visual Studio的"工具"菜单中选择"NuGet包管理器"，然后选择"管理NuGet包解决方案"来打开NuGet包管理器。在"已安装"选项卡中找到相关的包，选择卸载并删除相关的文件。然后重新安装包。

2. 更新NuGet：确保您使用的是最新版本的NuGet。可以通过在Visual Studio的"工具"菜单中选择"扩展和更新"来检查是否有可用的NuGet更新。如果有可用的更新，请安装并重启Visual Studio。

3. 检查包依赖项：检查被安装的包的依赖项是否有冲突或不兼容的情况。您可以查看包的说明文档或在NuGet网站上查找相关信息，以确定是否有其他包或版本要求。

4. 检查网络连接和代理设置：确保您的计算机可以正常访问NuGet包源。检查网络连接是否正常，并检查是否需要配置代理设置以便访问NuGet包源。

5. 重建解决方案：有时，在出现错误后，重新构建整个解决方案可以解决问题。尝试在Visual Studio中选择"生成"菜单，然后选择"重新生成解决方案"，然后再次尝试安装NuGet包。

如果以上方法仍然无法解决问题，建议您将完整的错误信息和相关细节提交给NuGet的支持团队，或者在相关论坛或社区中寻求帮助。