Blazor和WebAPI应用程序未运行以进行调试-无法运行您的项目。"；“运行命令”；属性未定义

我有一个运行.net standard 2.0的Blazor应用程序和一个运行.net core 3.1的WebAPI以及一个标准类库

应用程序编译并运行良好，直到昨天才停止编译并出现错误

无法运行您的项目。未定义“RunCommand”属性

Blazor和WebAPI的输出类型都是控制台应用程序，我设置了多个启动项目—WebAPI first和Blazor

我认为没有任何变化导致这个错误

你知道这是什么原因吗

更新

由于删除了obj和bin文件，我现在在VS中遇到以下错误-

严重性代码说明项目文件行抑制状态 命令“dotnet”时出现错误MSB3073 “C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.mono\3.1.0-preview3.19531.1\build\netstandard1.0.././tools/monoliinker/monoliinker.exe” -l none--disable opt unreachablebodies--verbose--strip security true--exclude feature com--exclude feature sre-v false-c link-u 链接-b真实-d “C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.mono\3.1.0-preview3.19531.1\build\netstandard1.0.././tools/mono/bcl/” -d“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.mono\3.1.0-preview3.19531.1\build\netstandard1.0../。/tools/mono/bcl/Facades/” -d“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.mono\3.1.0-preview3.19531.1\build\netstandard1.0.././tools/mono/framework/”-o“C:\Users\Matt\Desktop\auth\src\HeartOfGreen.BlazorClient\obj\Debug\netstandard2.0\blazor\linker/” -x“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.build\3.1.0-preview3.19555.2\targets\builtincbllinkerdescriptor.xml” -x“C:\Users\Matt\Desktop\auth\src\HeartOfGreen.BlazorClient\obj\Debug\netstandard2.0\blazor\linker.descriptor.xml” -“C:\Users\Matt.nuget\packages\blazored.localstorage\2.1.1\lib\netstandard2.0\blazored.localstorage.dll” -“C:\Users\Matt.nuget\packages\blazorinputfile\0.1.0-preview-00002\lib\netstandard2.0\blazorinputfile.dll” -“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.authorization\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.authorization.dll” -“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.blazor.dll” -a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.blazor.httpclient\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.blazor.httpclient.dll”-a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.components\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.components.dll” -a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.components.authorization\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.components.authorization.dll” -a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.components.forms\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.components.forms.dll” -a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.components.web\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.components.web.dll” -a“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.hosting\2.2.7\lib\netstandard2.0\microsoft.aspnetcore.hosting.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.hosting.abstractions\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.hosting.abstractions.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.hosting.server.abstractions\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.hosting.server.abstractions.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.http\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.http.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.http.abstractions\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.http.abstractions.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.http.extensions\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.http.extensions.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.http.features\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.http.features.dll” -“C:\Users\Matt.nuget\packages\microsoft.aspnetcore.metadata\3.1.0-preview3.19555.2\lib\netstandard2.0\microsoft.aspnetcore.metadata.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.aspnetcore.webutilities\2.2.0\lib\netstandard2.0\microsoft.aspnetcore.webutilities.dll” -a“C:\Users\Matt.nuget\packages\microsoft.bcl.asyncinterfaces\1.1.0-preview3.19551.4\lib\netstandard2.0\microsoft.bcl.asyncinterfaces.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.extensions.configuration\2.2.0\lib\netstandard2.0\microsoft.extensions.configuration.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.extensions.configuration.abstractions\2.2.0\lib\netstandard2.0\microsoft.extensions.configuration.abstractions.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.extensions.configuration.binder\2.2.0\lib\netstandard2.0\microsoft.extensions.configuration.binder.dll” -“C:\Users\Matt.nuget\packages\microsoft.extensions.configuration.environmentvariables\2.2.4\lib\netstandard2.0\microsoft.extensions.configuration.environmentvariables.dll” -“C:\Program Files\dotnet\sdk\NuGetFallbackFolder\microsoft.extensions.configuration.fileextensions\2.2.0\lib\netstandard2.0\microsoft.extensions.configuration.fileextensions.dll” -a“C:\Users\Matt.nuget\packages\microsoft.extensions.dependencyinjection\3.1.0-preview3.19553.2\lib\netstandard2.0\microsoft.extensions.dependencyinjection.dll”-a“C:\Users\Matt.nuget\packages\microsoft.extensions.dependencyinjection.Abstractations\3.1.0-preview3.19553.2\lib\netstandard2.0\microsoft.Ext