[ASPNETCORE] Add support for central package version management

[wing328]

based on #20192

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[Urganot]

I fixed it and opened up a new pr #20403 #20403

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/12636467556/job/35208601636?pr=20401

@Urganot can you please review the build errors when you've time?

[wing328]

FYI. Tested with optout and the output built locally without errors.

[Urganot]

I know what happens here.
Because there is no version in the csproj file, it tries to use the lowest possible. this obviously doesnt work.
In this case this is the correct behaviour though. when using centralized version management, you need to have a Directory.Packages.props file in your solution folder. in there you set the version of your packages. Without this file, it will fail. The problem is that generating this file into the generated project would defeat the purpose of this change because I want to control my versions from my non generated solution.
When using optout, it will put in the package versions. that is why it work in that case
I am not sure how this should be handled.

[wing328]

Without this file, it will fail. The problem is that generating this file into the generated project would defeat the purpose of this change because I want to control my versions from my non generated solution.

how do you use it in your non-generated solution?

maybe creating a simple HelloWorld C# project/app that depends on or consumes samples/server/petstore/aspnetcore-8.0-use-centralized-package-version-management ?