.NET MAUI迁移项目Windows构建报错：project.assets.json缺失目标框架

错误信息 #

构建时触发以下系列错误：

Assets file '..obj\project.assets.json' doesn't have a target for 'net6.0-android'. Ensure that restore has run and that you have included 'net6.0-android' in the TargetFrameworks for your project.

Assets file '..obj\project.assets.json' doesn't have a target for 'net6.0-windows10.0.22621.0'. Ensure that restore has run and that you have included 'net6.0-windows10.0.22621.0' in the TargetFrameworks for your project.

Assets file '..obj\project.assets.json' doesn't have a target for 'net6.0'. Ensure that restore has run and that you have included 'net6.0' in the TargetFrameworks for your project.

Assets file '..obj\project.assets.json' doesn't have a target for 'net6.0-ios'. Ensure that restore has run and that you have included 'net6.0-ios' in the TargetFrameworks for your project.

项目csproj核心配置 #

<PropertyGroup>
    <TargetFrameworks>net6.0-ios;net6.0-android;net6.0</TargetFrameworks>
    <TargetFrameworks Condition="$([MSBuild]::IsOSPlatform('windows'))">$(TargetFrameworks);net6.0-windows10.0.22621.0</TargetFrameworks>
    <OutputType>Exe</OutputType>
    <UseMaui>true</UseMaui>
    <SingleProject>true</SingleProject>
    <ImplicitUsings>enable</ImplicitUsings>   
    <Nullable>enable</Nullable>

    <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'ios'">14.2</SupportedOSPlatformVersion>
    <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'maccatalyst'">14.0</SupportedOSPlatformVersion>
    <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'android'">21.0</SupportedOSPlatformVersion>
    <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'windows'">10.0.17763.0</SupportedOSPlatformVersion>
    <TargetPlatformMinVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'windows'">10.0.22621.0</TargetPlatformMinVersion>
    <SupportedOSPlatformVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'tizen'">6.5</SupportedOSPlatformVersion>
    <DefaultLanguage>en</DefaultLanguage>
</PropertyGroup>

<PropertyGroup Condition="'$(TargetFramework)' == 'net6.0'">
    <OutputType>Library</OutputType>
</PropertyGroup>

已尝试的无效操作 #

• 清理项目
• 删除obj和bin目录
• 重新安装.NET MAUI工作负载

问题根源与解决方法 #

问题原因 #

全局PropertyGroup中设置版本号的条件判断代码干扰了MSBuild的目标解析流程：

<ApplicationDisplayVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) != 'ios'" >7.8.12844</ApplicationDisplayVersion>
<ApplicationVersion Condition="$([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) != 'ios'">2022092726</ApplicationVersion>

解决办法 #

将版本配置移至单独的、带有明确条件的PropertyGroup中，避免全局条件判断影响目标框架的恢复：

<PropertyGroup Condition="$(TargetFramework.Contains('-android')) and '$(Configuration)' == 'Release'">
    <ApplicationDisplayVersion>7.8.12844</ApplicationDisplayVersion>
    <ApplicationVersion>2022092726</ApplicationVersion>
</PropertyGroup>

修改后项目可在Windows Visual Studio中正常构建。

内容的提问来源于stack exchange，提问作者NPadrutt