In last two posts, Setting up development environment and Implenting custom DNN module, I have described you will do custom DNN module development. Now comes the fun part. How are you going to debug your module. Since your module gets loaded inside DotnetNuke site, the debugging requires change in your project settings.
When you used NANT build tool to create package for deployment, it uses release build options. So the assembly for your module does not have DEBUG option turned on in your site. What you can do is that do a DEBUG build of your project and replace module assemblies in BIN folder of your DNN site with the DEBUG version. Or you can make some change in NANT build file for your project to create a DEBUG package and then deploy that. If you are not comfortable with NANT build file, then go with the first option I mentioned.
One option you have it to change target start URL that gets invoked when hit F5 or choose Debug > Start Debugging menu option. To do that, bring up Properties of module project. Goto Web tab on the dialog box. You can select Use local web server or Use custom web server radio button and then specify the URL for your DNN installation. Now you will be able to break into your module.
Other option you have is to choose Debug > Attach to process menu option and then attach to ASP.Net process. And then put break points in your module to debug the problems.
If you are looking into debugging your DNN modules on live site then I will be discussing that in one of my later posts about how you can incorporate logging and diagnostics into your module.