.NET多目标框架构建错误：找不到NeutralResourcesLanguageAttribute

尝试将旧.NET Framework项目转为同时面向net481和net8.0-windows的双目标项目时，持续触发以下构建错误：

无法在程序集'C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.8.1\Facades\System.Runtime.dll'中找到类型'System.Resources.NeutralResourcesLanguageAttribute'。

已尝试删除bin和obj目录、重启Visual Studio等操作，均未解决问题。确认该属性存在于.NET 4.8.1中，但不清楚报错原因。

项目的.csproj文件内容如下：

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <UseWindowsForms>true</UseWindowsForms>
    <UseWpf>true</UseWpf>
    <Deterministic>false</Deterministic>
    <PlatformTarget>x64</PlatformTarget>
    <Platforms>x64</Platforms>
    <AssemblyName>JacobsRevitTools</AssemblyName>
    <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>
    <TargetFrameworks>net481;net8.0-windows</TargetFrameworks>
    <StartAction>Program</StartAction>
    <StartProgram>c:\Program Files\Autodesk\Revit 2025\Revit.exe</StartProgram>
    <Nullable>disable</Nullable>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
    <DefineConstants>$(DefineConstants);REVIT2019;REVIT2020;REVIT2021;REVIT2022;REVIT2023;REVIT2024;REVIT2025</DefineConstants>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="EPPlus" Version="7.4.0" />
    <PackageReference Include="Extended.Wpf.Toolkit" Version="4.6.1" />
    <PackageReference Include="NUnit" Version="4.2.2" />
    <PackageReference Include="SmartFormat.NET" Version="3.5.0" />
    <PackageReference Include="System.Configuration.ConfigurationManager" Version="8.0.1" />
    <PackageReference Include="System.Drawing.Common" Version="8.0.8" />
    <PackageReference Include="System.Resources.ResourceManager" Version="4.3.0" />
    <PackageReference Include="System.Runtime.Caching" Version="8.0.1" />
  </ItemGroup>
  <ItemGroup>
    <ProjectReference Include="..\JacobsToolsCommon\JacobsToolsCommon.csproj" />
    <ProjectReference Include="..\JacobsToolsUI\JacobsToolsUI.csproj" />
  </ItemGroup>
  <ItemGroup>
    <Reference Include="AdWindows">
      <HintPath>..\..\..\..\..\..\Program Files\Autodesk\Revit 2025\AdWindows.dll</HintPath>
      <Private>True</Private>
    </Reference>
    <Reference Include="RevitAPI">
      <HintPath>..\..\..\..\..\..\Program Files\Autodesk\Revit 2025\RevitAPI.dll</HintPath>
      <Private>True</Private>
    </Reference>
    <Reference Include="RevitAPIUI">
      <HintPath>..\..\..\..\..\..\Program Files\Autodesk\Revit 2025\RevitAPIUI.dll</HintPath>
      <Private>True</Private>
    </Reference>
  </ItemGroup>
  <ItemGroup>
    <Compile Update="Properties\Settings.Designer.cs">
      <DesignTimeSharedInput>True</DesignTimeSharedInput>
      <AutoGen>True</AutoGen>
      <DependentUpon>Settings.settings</DependentUpon>
    </Compile>
  </ItemGroup>
  <ItemGroup>
    <None Update="Properties\Settings.settings">
      <Generator>SettingsSingleFileGenerator</Generator>
      <LastGenOutput>Settings.Designer.cs</LastGenOutput>
    </None>
  </ItemGroup>
</Project>

解决方法 #

1. 移除不必要的System.Resources.ResourceManager包 #

在.NET Framework 4.8.1中，System.Resources.ResourceManager属于基础类库，无需通过NuGet引用。该包是为.NET Standard/.NET Core设计的，双目标时会干扰.NET Framework的程序集解析。直接删除对应的PackageReference：

<!-- 删除这一行 -->
<PackageReference Include="System.Resources.ResourceManager" Version="4.3.0" />

2. 为.NET Framework目标添加程序集绑定重定向（可选） #

如果删除包后仍有问题，可在项目中添加app.config（已存在则修改），添加绑定重定向确保System.Runtime指向正确的.NET Framework程序集：

<configuration>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Runtime" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.2.2.0" newVersion="4.0.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

3. 检查项目引用的依赖项是否兼容双目标 #

确认所有PackageReference和ProjectReference都支持net481和net8.0-windows。例如，部分旧包可能仅支持.NET Framework，需升级到兼容版本；或者通过条件引用为不同目标框架指定合适的包版本：

<PackageReference Include="Extended.Wpf.Toolkit" Version="4.6.1" Condition="'$(TargetFramework)' == 'net481'" />
<PackageReference Include="Extended.Wpf.Toolkit" Version="5.0.0" Condition="'$(TargetFramework)' == 'net8.0-windows'" />

4. 清理并重新生成解决方案 #

• 删除所有项目的bin和obj目录
• 在Visual Studio中执行清理解决方案，再执行重新生成解决方案
• 若仍有问题，尝试使用命令行构建：

  dotnet clean
  dotnet build --configuration Debug
  

内容的提问来源于stack exchange，提问作者sean2000