Desktop .NET Framework

The C# extension supports limited full .NET framework debugging. It can only debug 64-bit applications with portable PDBs.

To enable the Desktop CLR debugger, change the configuration type in launch.json to be "clr" instead of "coreclr" and program should be pointing at the exe (NOT a .dll).

For unit tests, this can be done thusly:

1. File->Preferences->Settings
2. Open "CSharp: Unit Test Debugging Options"
3. Set the 'type' to 'clr' (see settings.json example below)
4. NOTE: For MSTest projects, also see Forcing MSTest projects to use a 64-bit worker section.

launch.json example

{
   ...
   "type": "clr",
   "program": "path\\to\\program.exe",
   ...
}

More information about debugging desktop .NET Framework can be found here, https://stackoverflow.com/questions/47707095.

settings.json example

{
    ...
    "csharp.unitTestDebuggingOptions": {
        "type": "clr"
    }
}

Forcing MSTest projects to use a 64-bit worker

Some versions of MSTest will use an x86 worker process to run tests, which is not supported by the debugger. This can result in error messages like: Unable to start program '<some-path-here>\\testhost.net472.x86.exe'. Unknown Error: 0x80131c30 or Unable to start program '<some-path-here>\\testhost.net472.x86.exe'. The .NET debugger can only debug x64 processes..

To fix this:

1. Create a '.runsettings' file such as the following
2. Add/modify a 'settings.json' file in the root of the workspace that points at the .runsettings file: "omnisharp.testRunSettings": "C:\\My-workspace-root-here\\UseX64Worker.runsettings"

Example .runsettings file

<?xml version="1.0" encoding="utf-8"?>
<RunSettings>
  <RunConfiguration>
    <TargetPlatform>x64</TargetPlatform>
  </RunConfiguration>
</RunSettings>