Object based languages don't support Inheritance where as object oriented supports. C# is a object oriented language due to it supports inheritance and asp.net is not a language it is a technology
If the language supports only 3 features i.e. (data encapsulation, data abstraction $ polymorphism).then it is said to be object based programming language. If the language supports all the 4 features i.e. (encapsulation, abstraction, polymorphism $ also inheritance )..then it is said to be object oriented programming language.