Add support for setting multiple startup projects

[bording]

While support for specifying a single startup project was added by setting DefaultStartup="true" in the Project element, it does not work for specifying multiple startup projects, as I pointed out in my comment on the original issue.

It would be great it if I could specify DefaultStartup="true" on multiple projects in the slnx file and it would be respected.

[michael-hawker]

Is this basically related to the Multiple Startup feature? As otherwise, what's the expectation/scenario here?

Should there be a difference between "Default" and "Multiple"?

[bording]

Is this basically related to the Multiple Startup feature? As otherwise, what's the expectation/scenario here?

Should there be a difference between "Default" and "Multiple"?

Yes, this is related to multiple startup. I want to be able to mark the projects in some way in the slnx file, and then have all of those projects start when F5 is pressed.

Right now to achieve this, we've been using a tool to edit a .suo file and including that file in the artifact to ensure the desired projects are configured to startup when the solution is opened.

[richardstanton]

The .slnLaunch configuration file should make it possible to specify startup project profiles without updating the .suo file. These can be checked into the repo to be shared with other users. The .slnx file isn't really designed to store that complex a configuration.

https://learn.microsoft.com/en-us/visualstudio/ide/how-to-set-multiple-startup-projects?view=visualstudio