Visual Studio 目标框架灰显

Question

I'm using Visual Studio 2019 v16.8.5 and this morning I found that my solution which targets .net5.0 could not build and had the error:

The TargetFramework value .net5.0-windows' was not recognized. It may be misspelled. If not, then the TargetFrameworkIdentifier and/or TargetFrameworkVersion properties must be specified explicitly.

If I go into the project properties the Target Framework combobox is greyed out. If I create a new solution, the combobox is still greyed out (however, the new solution targets .net3.1 and builds fine).

I didn't have this problem yesterday and I haven't installed any updates. I've also checked I don't have any global.json files in my solution as suggested in a similar post.

My property group is as follows:

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

  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net5.0-windows</TargetFramework>
    <UseWPF>true</UseWPF>

    <RootNamespace>Drain</RootNamespace>

    <ApplicationIcon>icon_vRx_icon.ico</ApplicationIcon>

    <Platforms>AnyCPU;x64</Platforms>

    <AssemblyVersion>0.0.0.1</AssemblyVersion>

    <FileVersion>0.0.0.1</FileVersion>

    <AutoGenerateBindingRedirects>true</AutoGenerateBindingRedirects>
  </PropertyGroup>

Any suggestions what might have happened?

Answer 1

Sorry to reply you so late:

Currently .Net 5.0 is not supported, it is recommended that you upgrade to .Net 6.0 as soon as possible.

There is no problem in copying your property group under my 2019 16.11.13 version , you could try to update the version.

I suggest you go to the visual studio installer to check whether the .Net 5.0 Runtime is installed correctly (you could try to reinstall).

• Finally, I want to ask, will you encounter the same problem when you create a new.Net 5.0 WPF project?