Difference between Debugger.Launch and Debugger.Break

More subtle differences:

1. If a debugger is already attached, Debugger.Launch is a nop; whereas Debugger.Break will always break into the debugger.

2. Launching a debugger does not actually break into the debugger. For example, in Visual Studio, Debugger.Launch will attach a debugger to the running process, but then you still need to do a Debug | Break in Visual Studio to actually break under the debugger.

I'm not sure if anyone actually tried what's the difference or if it's different between .NET Framework and .NET 5 but this is the behavior when I test it:

After clicking OK VS will break on Debugger.Launch() (despite other answerers saying it will not):

However the debugger will not break on Debugger.Launch() if it is already attached.

If I pack my project as a dotnet Tool everything is the same except it doesn't know where to break:

TL;DR: In .NET 5:

With debugger attached:

• .Launch() will do nothing
• .Break() will break

Without debugger attached:

• .Launch() will ask to attach a debugger and if you do, it will break at .Launch()
• .Break() will do nothing (no exceptions)

Example.csproj:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>

</Project>

Program.cs:

using System;
using System.Diagnostics;

Console.WriteLine("Before break");

Debugger.Break();

Console.WriteLine("After break");

Console.WriteLine("Before Launch");

Debugger.Launch();

Console.WriteLine("After Launch");