如何以编程方式更新Visual Studio项目中的项目引用

Question

I have a file structure like the following:

- binaries
   - binary1.dll
- dev
   - <developer-name>
      - a.csproj
-trunk
    - a.csproj

Developers who need to work on a.csproj will create a branch in dev and they will work from there. Our projects need to have a reference to binary1.dll in the binaries directory.

If the reference is a relative path (the Visual Studio default) then the path will not work both for the project in trunk and the project in the developer's branch.

To work around this problem I thought of creating an environment variable and using that in the project file instead:

<Reference Include="binary1">
   <HintPath>$(MY_ENV_VAR)\binary1.dll</HintPath>
</Reference>

This works perfectly, but I wanted to help developers add references more easily, so I wrote a program that will convert relative paths that point to binary1.dll (for example, from the dev branch a.csproj it would change the path ../../binaries/binary1.dll to $(MY_ENV_VAR)\\binary1.dll ) but I have not figured out how to get that to work.

If I use a pre-build event, the project is already loaded into memory and the event return an error because it cannot write the project file.

Then I realized that I could override MSBuild targets, and attempted with the targets: BeforeCompiler , AfterCompiler , BeforeBuild , AfterBuild and in all of them the project is already locked.

Then I ran into this answer and I modified my code to call the executable in the GenerateApplicationManifest target, but that one doesn't seem to call the executable at all.

Some other ideas that I have been playing with are creating a new project that does the updating of the second project and have a link between them, but that would duplicate the number of projects.

I could also just change the depth of trunk, but that only hides the problem and doesn't really solve it. When developers create a branch inside their dev branch to work on different features or bugs then I have the same problem all over again.

There might also be another feature which fixes this in a more elegant way, but I haven't been able to find anything.

So my question: How do I get MS Build or pre-build events to modify a CS project?

Answer 1

I found a way to do this. The issue was that the Visual Studio process itself was locking the project, but Visual Studio could overwrite the file. I ended up modifying a.csproj to include:

<Target Name="BeforeBuild">
    <Exec Command="UpdateReferences.exe" /> <!-- This creates the $(ProjectPath).new file -->
    <Move SourceFiles="$(ProjectPath).new" DestinationFiles="$(ProjectPath)" />
  </Target>