Support for precompilation

[Yozer]

For performance reasons and huge cold start: it's a crucial part for an application with a lot of pages and user controls.
While aspnet_compiler.exe sources are not public they can be "previewed" and it's nothing more than just command line wrapper around ClientBuildManager which is already ported to net9.0.

Maybe a good approach would be to create similar build task like https://github.com/webformsforcore/WebFormsForCore/tree/main/src/WebFormsForCore.Build to execute on Release builds to precompile entire application and save produced assemblies that later could be loaded.

[simonegli8]

I've tried to look into this, and so far cloned the source of aspnet_compiler.exe. But there are some problems to it, as the old aspnet_compiler.exe fails on SDK-style projects, and it'd be needed on projects that dual compile for net48 & net8.0.
So I'm not sure on how to proceed with this, I don't know if it's feasible that easily.

[Yozer]

In my project we call aspnet compiler by hand in csproj on Release builds.
I think it should be possible to call aspnet_compiler.exe for net48 and something like aspnet_compiler_netcore.exe for net9.0.
I'm happy to take a look at this.

[simonegli8]

I've introduced WebFormsForCore.AspNetCompiler project with the decompiled source code of aspnet_compiler.exe. But it is not working, also the old aspnet_compiler is not working on the TestApp, probably because it's an SDK style project. I don't know how to make work this any further, it seems this is not such an easy task to get aspnet_compiler working with WebFormsForCore. Next week I'll be busy with my job, I might look into this next Saturday or from August on I'll be in Nicaragua and only work part time, then I might find some time for this.
Also, when using net8.0 the build directory is only defined in the csproj, and for net8.0 it is not the default "bin" folder but "bin_dotnet", but this is not hardcoded, WebFormsForCore just looks for the parent folder of the assemblies and uses that as application base folder, so the dll's can also be in something else than "bin_dotnet".

[Yozer]

Honestly I found it much easier to have two csprojs: old, legacy csproj and new csproj in sdk-format at the same time.
You can easily have them in the same directory, the only caveat is that you need to override obj folder as well to something like obj_dotnet.
I can take a look on that but first wanted to fix some other issues (except bundles, open PRs I also found that static WebMethods are not working)