How can I use BeforeBuild and AfterBuild targets with Visual Studio 2017?

Question

After upgrading to a csproj to use Visual Studio 2017 and Microsoft.NET.Sdk, my "BeforeBuild" and "AfterBuild" targets are no longer running. My file looks like this:

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

  <PropertyGroup>
    <TargetFramework>net46</TargetFramework>
  </PropertyGroup>

  <!-- my targets that don't run -->
  <Target Name="BeforeBuild">
      <Message Text="Should run before build" Importance="High" />
  </Target>

  <Target Name="AfterBuild">
      <Message Text="Should run after build" Importance="High" />
  </Target>

</Project>

Bast

Answer 1

The associated MSBuild git issue recommends not using BeforeBuild/AfterBuild as task names going forward, instead name the task appropriately and wiring up against targets

<Project Sdk="Microsoft.NET.Sdk"> 
  <PropertyGroup>
    <TargetFramework>net46</TargetFramework>
  </PropertyGroup>

  <!-- Instead of BeforeBuild target -->
  <Target Name="MyCustomTask" BeforeTargets="CoreBuild" >
      <Message Text="Should run before build" Importance="High" />
  </Target>

  <!-- Replaces AfterBuild target -->
  <Target Name="AnotherCustomTarget" AfterTargets="CoreCompile">
      <Message Text="Should run after build" Importance="High" />
  </Target>    
</Project>

This gets you an idiomatic VS 2017 project file, but which targets you trigger before/after is still a matter of some debate at this time

Katharina

this also works for VS2019, should be accepted answer – Tortuosity

are you sure this is correct? To run something after the build shouldn't it be BeforeTargets="CoreCompile"? see #44044418 – Trail

@Goswin, may be but this information was lifted directly from comments in the git issue – Katharina

What is the difference between "Build" and "CoreCompile"? IOW, if I have AfterTargets="Build" in a nuspec file in VS2015 would that need to be changed if I want to use that nuget in VS2019 to AfterTargets="CoreCompile" – Tortuosity

Answer 2

When you specify Project Sdk="Microsoft.NET.Sdk", you are using "implicit top and bottom imports". This means there is an invisible Import to Microsoft.NET.Sdk/Sdk.targets at the bottom of your csproj file which is overriding the "BeforeBuild" and "AfterBuild" targets.

You can fix this by using explicit imports so you can control the import order.

<Project>

  <Import Project="Sdk.props" Sdk="Microsoft.NET.Sdk" />

  <PropertyGroup>
    <TargetFramework>net46</TargetFramework>
  </PropertyGroup>

  <Import Project="Sdk.targets" Sdk="Microsoft.NET.Sdk" />

  <!-- add your custom targets after Sdk.targets is imported -->
  <Target Name="BeforeBuild">
      <Message Text="Should run before build" Importance="High" />
  </Target>

  <Target Name="AfterBuild">
      <Message Text="Should run after build" Importance="High" />
  </Target>

</Project>

Bast

IS it possible to move TargetFramework property to external props file? When I tried doing that, Visual Studio gives me a "one-way upgrade" error. – Highlander

@AlexI try opening a new SO question. That's separate from what this answer is about – Bast

Just did: #45155154 – Highlander

Answer 3

In the already mentioned GitHub issue Rainer Sigwald provides much shorter and elegant solution:

<Target Name="CustomBeforeBuild" BeforeTargets="BeforeBuild"> ... </Target>
<Target Name="CustomAfterBuild" AfterTargets="AfterBuild"> ... </Target>

Looks odd, but works fine.

Soldo