Someone just pointed to the link with the source code
http://msdn.microsoft.com/en-us/library/aa478948.aspx I haven't checked it yet.

>>Hi everybody,
>>
>>The new question, if I may.
>>
>>1. How can I see the actual code of the system classes?
>
>This only recently became available. It requires VS 2008 to do this automatically, here's a link which goes into detail about how to get it all installed:
>
>http://weblogs.asp.net/scottgu/archive/2008/01/16/net-framework-library-source-code-now-available.aspx
>
>If you don't/can't go that route, download Reflector from www.aisto.com/roeder/dotnet/ - it will let you open any .NET assembly and it will let you view a decompiled version of the source code.
>
>>2. Is the common practice to just trap the exceptions, say, if I want to add a user(s) to the role(s) and some of them are already in that role, I'm currently getting an exception with some helpful message.
>
>Yes, it's standard practice to only trap exceptions which you can handle, which usually isn't just "Exception", but a specific type of exception (or exceptions). Having said that, sometimes you have to capture the generic "Exception" type because no other (more specific exception) type is available.