Is C# programming language a prerequisite for learning ASP.NET?

I think YES! Nowadays ASP.NET developers are dealing with c# as coding language and you will find much more help on the net on ASP.NET + C#. I recommend to learn c# for ASP.NET.

Yes, I too think that C# is the need of the hour. Its somewhat like Java. It means that if you know Java, you may take lesser time to learn C#. Also, its fun coding in C#!
So, Enjoy!

If you sepend more time on something, you become more powerful to control it.
You will learn something in 1 month but you won't be professional.
C# and ASP.NET has close relation if you want to work as a web developer and not a web designer.

Actually I like seeing how all the above solution providers seem to agree that C# is the language of choice and that's what I also advocate. If you should already have some proficiency in VB.NET however, that might be the quicker way for you to go.
I don't want to get entangled in this ongoing VB.NET dispute, but merely giving my opinion that learning one new thing (ASP.NET) is quite a task in itself and you would have a real advantage if you only needed to concentrate on one difficult task instead of two.

Best regards,

—MRB

You can.

Learn anything in Web
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Education Needed[^]

And another one
What is a good free site for a child to learn simple coding?[^]