Build depends on AfterBuild Microsoft.Common.targets

Question

I'm trying to figure out when the different targets are run. But I'm a little confused when it comes to the AfterBuild target, it's comment is "Redefine this target in your project in order to run tasks just after Build". But when I look at what Build depends on I see:

<BuildDependsOn>
        BeforeBuild;
        CoreBuild;
        AfterBuild
 </BuildDependsOn>

Dos not this mean that the Build target runs after "AfterBuild" or am I missing something here? I'm new to Build so maybe I have missed something trivial.

Answer 1

You should do some further research in the same file (just do a search on BuildDependsOn in a text editor): you'll see the Build target itself is just a stub that looks something like this:

<Target
  Name="Build"
  DependsOnTargets="$(BuildDependsOn)"/>

So when one calls msbuild /t:Build, msbuild looks up the build target and sees it has a DependsOnTargets property whith the value BeforeBuild;CoreBuild;AfterBuild (note that is a list). Since DependsOnTargets is always executed before the target itself, all targets listed therein executed first in the order listed. Only then the Build target itself is executed (so yes, that effectively happens after AfterBuild). But the Build target itself actually doesn't do anything: compiling etc all happens in CoreBuild so by the time it's invoked everything is done already.

This might seem odd at first, but it's actually a very expandable way to make targets depends on each other and define the order in which they run. (there's DependsOn, but also BeforeTargets and AfterTargets) So suppose you want a target that for clarity effectively runs after Build, you can use the same principle:

<Target Name="MyTarget" AfterTargets="Build">
  ...
</Target>

Note this is actually the preferred way: in large projects it's not reliable to override AfterBuild since you don't know if somebody else also did it already, and overriding it in multiple places results in only the last one found to be called.