dotnet core 2.0 - programmatically attach the VS2017 debugger to a process

Question

In my dotnet core 2.0 application I re-launch the same application in a different process (with some different arguments) at a certain point. I want to be able to programmatically attach the current Visual Studio (2017) debugger to the new process.

Here is an example of how it is done in full framework but for starters the Marshal.GetActiveObject method doesn't appear to exist.

Is there a different way to achieve this in dotnet core 2.0? Or is it just not possible?

Answer 1

While this is changing, .Net Core was envisioned to be as cross-platform as possible and originally left out many 'windows-only' methods. That said, you can still call into the underlying windows functions using P/Invoke:

[DllImport("oleaut32.dll", PreserveSig = false)]
static extern void GetActiveObject(ref Guid rclsid, IntPtr pvReserved,
    [MarshalAs(UnmanagedType.IUnknown)] out object ppunk);

[DllImport("ole32.dll")]
static extern int CLSIDFromProgID(
    [MarshalAs(UnmanagedType.LPWStr)] string lpszProgID, out Guid pclsid);
....

// Replace XX with the correct version
CLSIDFromProgID($"VisualStudio.DTE.XX.0", out var classId); 
GetActiveObject(ref classId, default, out dte);