Stepping in to .Net source code with VS2008 SP1

With the release of Visual Studio 2008 SP1, a new feature was introduced and touted, but not turned on by default. This feature allows you to step in the .Net source code while debugging in Visual Studio. If at any point within your code, you can look at the callstack and traverse all the way down to the creation of the current running thread. Very cool!

To do this, you just have to change a couple default options.

First, go to Tools -> Options. Choose “Debugging” from the left-hand side menu, and uncheck the Just-my-code option. Next you’ll want to check “Enable .Net framework source stepping”.

Hit OK, and the symbols should* start to download from Microsoft’s servers, complete with developer comments.

The first time view the code you will be prompted to accept their license agreement.

*If the symbols didn’t download when you hit OK, you can go to the Symbols submenu and choose to download the symbols explicitly from the Microsoft servers. I’ve noticed this happening on a coworker’s machine once already.