How to step into NHibernate code

In 10 minutes you can be stepping into NHibernate code to see exactly what’s it’s doing with your project. Here’s how to do it:

1) Go download the NHibernate source code from here. As I’m writing this, the latest release version is 1.2.0.GA. (I’m assuming here that you already have NHibernate set up to work with your application.)
2) Unzip the source to a location on your machine.
3) Open the NHibernate.sln file in Visual Studio that corresponds to the version of the .NET framework that you are using (1.1 or 2.0). If you really want to build everything, including the Iesi.Collections assemblies and all the unit tests, then open the NHibernate-Everything.sln file, but for me this is overkill because I usually only want to step into the NHibernate code. If you build NHibernate-Everything.sln, you’ll have to have NUnit 2.2.8 installed to build the unit test projects.
4) Make sure the Debug configuration is selected and build the entire solution.
5) If you open the \src\NHibernate\bin\Debug-2.0 (or Debug-1.1) folder, you will see all of the assemblies along with the .pdb files (if you just build the NHibernate-1.1/-2.0.sln file, you will only see one .pdb — NHibernate.pdb). Copy all of the .dll and .pdb files to the location where you currently have your NHibernate .dll files in your project.

Now when you debug your project, you should be able to step into NHibernate code!

Obvious caveat: we’re assuming that the source code that you downloaded is the exact same code that they used to build the release assemblies. I don’t see any reason why this wouldn’t be the case, but I’ve run into this problem before with other third party packages (like Infragistics NetAdvantage controls). So it might not be a bad idea to remove the debug NHibernate dlls when you’re done stepping into them and put the release dlls back in so that you don’t get burned.

Hope this helps! If you encounter any problems with this process, please let me know.