But how Asp.Net 2.0 programmers usually design and implement
their pages?
Any way they like.
They have asp (html page) and e.g. C# file for data structures
and data manipulation. But how it's organized if MVC is not used
and there are no Controllers?
ASP.NET is an event driven model, like Visual Basic. Events are dispatched
to functions that handle those events. In a way, the code behind is a form
of controller, but most people don't really consider it that way because
teh ASP.NET runtime hides much of that from you.
Aren't there any one entrypoint to consentrate user's request from browser?
That happens behind the scenes in the ASP.NET Page class, which is an
ASP.NET HttpHandler. Its job is to figure out what functions to call based
on the events the user generates.
For ASP.NET 1.1, Microsoft offered a downloadable MVC framework called the
User Interface Process Application Block, but this has been discontinued
for .NET 2.0. There is rumored to be something to replace it in the works,
but nothing concrete yet that I'm aware of. UIPAB was a bit too cumbersome
and tried to unify Windows Forms and ASP.NET, and it just didn't work
right.
As I said, there are a number of third party solutions out there.
http://www.c-sharpcorner.com/Code/2003/Feb/MVCDesign.asp
http://www.dmbcllc.com/Articles/WebDevelopment/MVCForASPNET/tabid/83/Default.aspx
etc.. google is your friend.
You might also want to read some opinions on the other side of the fence:
http://codebetter.com/blogs/eric.wise/archive/2004/08/13/21976.aspx