Azure Functions v4迁移调试报错：无法加载指定程序集

问题背景 #

已完成Azure Function从v2到v4的迁移，项目升级至.NET6，修复了包引用编译错误，解决方案包含3个适配.NET6和v4的项目，但调试时抛出System.IO.FileNotFoundException，提示无法加载Microsoft.Extensions.Configuration.Abstractions, Version=7.0.0.0。

项目配置 #

Azure Function项目 #

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <AzureFunctionsVersion>v4</AzureFunctionsVersion>
  </PropertyGroup>
  <ItemGroup>
      <PackageReference Include="Azure.Messaging.ServiceBus" Version="7.11.1" />
      <PackageReference Include="Azure.Messaging.EventHubs" Version="5.7.5" />
      <PackageReference Include="DocumentFormat.OpenXml" Version="2.18.0" />
      <PackageReference Include="Microsoft.Azure.WebJobs" Version="3.0.33" />
      <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.EventHubs" Version="5.1.2" />
      <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.ServiceBus" Version="5.8.1" />
      <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
      <PackageReference Include="Microsoft.Extensions.Azure" Version="1.6.0" />
      <PackageReference Include="Microsoft.Extensions.Configuration" Version="7.0.0" />
      <PackageReference Include="Microsoft.Identity.Client" Version="4.48.1" />
      <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="4.1.3" />
  </ItemGroup>
  <ItemGroup>
    <ProjectReference Include="..\PCM.1.z\x.1.z.csproj" />
  </ItemGroup>
  <ItemGroup>
    <Compile Update="2.cs">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Compile>
    <Compile Update="1.cs">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Compile>
    <Compile Update="3.cs">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </Compile>
  </ItemGroup>
  <ItemGroup>
    <None Update="host.json">
      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
    </None>
    <None Update="local.settings.json">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
      <CopyToPublishDirectory>Never</CopyToPublishDirectory>
    </None>
  </ItemGroup>
</Project>

第二个项目 #

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

  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
      <PackageReference Include="Azure.Messaging.ServiceBus" Version="7.11.1" />
      <PackageReference Include="Azure.Messaging.EventHubs" Version="5.7.5" />
      <PackageReference Include="Microsoft.ApplicationInsights" Version="2.21.0" />
      <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.2.0" />
      <PackageReference Include="Microsoft.Azure.Devices" Version="1.38.2" />
      <PackageReference Include="Microsoft.Azure.WebJobs" Version="3.0.33" />
      <PackageReference Include="SendGrid" Version="9.28.1" />
      <PackageReference Include="StackExchange.Redis" Version="2.6.80" />
      <PackageReference Include="Twilio" Version="6.0.1" />
      <PackageReference Include="UnitsNet" Version="4.149.0" />
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\x.1.w\x.1.w.csproj" />
  </ItemGroup>

</Project>

第三个项目 #

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

  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="7.0.0" />
  </ItemGroup>

</Project>

异常信息 #

Exception thrown: 'System.IO.FileNotFoundException' in Microsoft.Azure.WebJobs.Host.dll.
An exception of type 'System.IO.FileNotFoundException' occurred in Microsoft.Azure.WebJobs.Host.dll but was not handled in user code
Could not load file or assembly 'Microsoft.Extensions.Configuration.Abstractions, Version=7.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'.

修复方案 #

1. 统一Microsoft.Extensions系列包版本 #

Microsoft.NET.Sdk.Functions 4.1.3依赖Microsoft.Extensions.Configuration.Abstractions 6.x版本，当前项目中使用的7.0.0版本不兼容，需降级调整：

• 将Azure Function项目中的Microsoft.Extensions.Configuration从7.0.0改为6.0.1
• 将Microsoft.Extensions.Azure从1.6.0改为1.5.1（适配.NET6，依赖6.x的Extensions包）

2. 降级Entity Framework Core版本 #

.NET6需搭配EF Core 6.x版本，将第三个项目中的Microsoft.EntityFrameworkCore.SqlServer从7.0.0改为6.0.25：

<PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="6.0.25" />

3. 清理重建项目 #

• 删除所有项目的bin和obj目录
• 执行dotnet restore重新还原依赖包
• 重新编译并启动调试

4. 强制统一依赖版本 #

若仍存在版本冲突，在Azure Function项目的<ItemGroup>中添加直接引用，强制指定版本：

<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="6.0.1" />

5. 验证本地工具版本 #

确保本地Azure Functions Core Tools为v4版本，执行func --version查看，若版本过低则升级至最新v4版本。

内容的提问来源于stack exchange，提问作者Sammy