is the knowledge of ado.net is necessory for learning asp.net
and to build web in asp.net

Developing any web site that requires access to an external data file you are using ADO.NET. Also, if the web site is Data-Driven it would be to your advantage to know ADO.NET. In learning ASP.NET, there are sections that will address ADO.NET, however I enjoy developing,modeling and programming relational and object oriented databases, so my knowledge of ADO.NET is invaluable. However the decision is left up to you as a developer.

Hope this helps.

No. You do not need to know ADO.net at all to do a lot with asp.net. And if you do find that you need to use a database, learning ADO.net is not difficult and there are lots of resource and books on the topic.

Have fun.

Woody Z http://www.learntoprogramnow.com