How to debug aspnetcore source code?

[jackletter]

I'like debug source code,but how debug this code in Visual Studio

EDIT by @Rick-Anderson for those who get here via search See https://github.com/dotnet/AspNetCore.Docs/issues/4155

[Ronkiro]

Just set breakpoints and then run your application

[jackletter]

I mean debugging the source code of aspnetcore, not my code

[xsoheilalizadeh]

@jackletter, Currently you're able to debug the ASP.NET Core source code, take a look at these links:

Debugging ASP.NET Core 2.0 Source Code Debugging third-party code with Rider

[jackletter]

I try to use symbols to debug the source code, but the prompt is: Https://msdl.microsoft.com/download/symbols: no symbols found on the symbol server. Https://symbols.nuget.org/download/symbols: no symbols found on the symbol server. Here are my project settings:

[Pilchie]

@dotnet/aspnet-build - how is this currently supposed to be working? Also, @jackletter, it looks like you're running on .NET Core 2.0 which has been out of support for a long time. I recommend upgrading to 3.1, or if that is too big a jump immediately, at least 2.1. Both 2.1 and 3.1 are LTS releases.

See https://dotnet.microsoft.com/platform/support/policy/dotnet-core for details.

[dougbu]

how is this currently supposed to be working?

For 2.0, the instructions at https://www.stevejgordon.co.uk/debugging-asp-net-core-2-source look reasonable. I suspect the out-of-support 2.0 symbols have simply expired and been removed from MSDL.

For anything recent (3.0.0 and on), all of the symbols should be available on MSDL.

There's a symbol checker somewhere in Arcade we might be able to use to confirm the 2.1 symbols are still where we expect (MSDL or perhaps the old NuGet symbol server).

[jackletter]

When I tried version 3.1, the same thing happened： Does the symbol not exist on the server?

[dougbu]

It's possible the issue is geo-distribution of the symbol files but I'm not positive. Could you please provide the exact version information of the files you're checking? I'll check in the next couple of days.

[jackletter]

region 程序集 Microsoft.Extensions.Hosting, Version=3.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60

// C:\Program Files\dotnet\packs\Microsoft.AspNetCore.App.Ref\3.1.0\ref\netcoreapp3.1\Microsoft.Extensions.Hosting.dll

endregion

I look for assemblies in this order:

What is a reference assembly? Can't find a symbol related to it?

[dougbu]

What is a reference assembly? Can't find a symbol related to it?

See https://docs.microsoft.com/en-us/dotnet/standard/assembly/reference-assemblies

The information I asked for is only available at runtime. Check the Modules window (Debug -> Windows -> Modules aka Ctrl+D, M) when debugging your application. I can't read the complete Version or Timestamp columns in the screenshots provided earlier.

[jackletter]

[dougbu]

I checked everything in the 3.1.1 shared framework and all looks well here in Redmond e.g.

Checking file  C:\Temp\SymbolTest\8cfd4d4d-149a-44d7-9272-1078a500d005\content\shared\Microsoft.AspNetCore.App\3.1.1\Microsoft.Extensions.Hosting.dll ... Symbols found on MSDL (NGen PDB) and SymWeb (NGen PDB)

I'll check 2.1 later today.

[dougbu]

Did a spot check of our 2.1 and 2.2 packages and confirmed their symbols are also available on MSDL. (Minor detail: You don't need the NuGet symbol source for our symbols.)

I also debugged a default ASP.NET Core MVC application and successfully downloaded all of the symbols:

The issue you're having @jackletter is likely a networking problem, either geo-location (as I mentioned earlier) or an intervening proxy refusing to connect to the symbol servers and (oddly) returning a 404.

[Pilchie]

Closing as we can't seem to reproduce this issue locally.

[fangqifan]

@jackletter you need SS or V2ray to bypass GFW