Start a build from within the IDE

Custom project systems must use IVsBuildManagerAccessor to start builds. This article describes the reasons for this requirement and outlines the procedure.

Parallel builds and threads

Visual Studio allows parallel builds, which requires mediation for access to common resources. Project systems can run builds asynchronously, but such systems must not call build functions from within call-backs.

If the project system modifies environment variables, it must set the NodeAffinity of the build to OutOfProc. This requirement means that you cannot use host objects, since they require the in-proc node.

Use IVSBuildManagerAccessor

The code below outlines a method that a project system can use to start a build:

public bool Build(Project project, bool isDesignTimeBuild)
{
    // Get the accessor from the IServiceProvider interface for the
    // project system
    IVsBuildManagerAccessor accessor =
        serviceProvider.GetService(typeof(SVsBuildManagerAccessor)) as
        IVsBuildManagerAccessor;
    bool releaseUIThread = false;
    try
    {
        if(accessor != null)
        {
            // Claim the UI thread under the following conditions:
            // 1. The build must use a resource that uses the UI thread
            // or,
            // 2. The build requires the in-proc node AND waits on the
            // UI thread for the build to complete
            if(NeedsUIThread)
            {
                int result = accessor.ClaimUIThreadForBuild();
                if(result != S_OK)
                {
                     // Not allowed to claim the UI thread right now
                     return false;
                }
                releaseUIThread = true;
             }
             if(isDesignTimeBuild)
             {
// Start the design time build
                  int result = accessor.BeginDesignTimeBuild();
                  if(result != S_OK)
                  {
                      // Not allowed to begin a design-time build at
                      // this time. Try again later.
                      return false;
                  }
             }
         }
         bool buildSucceeded = false;
         // perform project-system specific build set up tasks
         // Create your BuildRequestData
         // This assumes a IHostServices variable (hostServices) set
   // to your host services. If you don't use a project instance
         // (you build from a file for example) then use another
         // constructor.
         BuildRequestData requestData = new
             BuildRequestData(project.CreateProjectInstance(),
             "myTarget", hostServices,
             BuildRequestData.BuildRequestDataFlags.None);
         // Mark your your submission as Pending
         BuildSubmission submission =
              BuildManager.DefaultBuildManager.
              PendBuildRequest(requestData);
         // Register the loggers in BuildLoggers
         if (accessor != null)
         {
               foreach (ILogger logger in BuildLoggers)
               {
                    accessor.RegisterLogger(submission.SubmissionId,
                        logger);
               }
         }
         BuildResult buildResult = submission.Execute();
         return buildResult;
     }
     // Clean up resources
     finally
     {
         if(accessor != null)
         {
             // Unregister the loggers, if necessary.
             accessor.UnregisterLoggers(submission.SubmissionId);
             // Release the UI thread, if used
             if(releaseUIThread)
             {
                  accessor.ReleaseUIThreadForBuild();
             }
             // End the design time build, if used
             if(isDesignTimeBuild)
             {
                  accessor.EndDesignTimeBuild();
             }
         }
     }
}