>>>Hi,
>>>I would like to subclass another web form including its UI (aspx) instead of only code behind web page. How could I do so ?
>>>
>>>Thank you
>>
>>There is no simple visual subclassing in ASP.NET The simplest way could be to move the part you want to re-use to the User Control. Making the page to be your parent class is much more involved process.
>
>One of the giant leaps backward for ASP.NET.

Yes, here we're lacking VFP simplicity of turning working form (page) into a class.