Question

In C++ we can declare a class in a .h file and can have the definitions for functions across multiple files. Is this concept same by using partial keyword with classes in C#?

Answer 1

No it’s not. The partial keyword in C# allows you to add new methods and members to a class. In c++, once a class is defined in a header, you need to change that header in order to change the class, you can’t just declare new methods/members in a different header.

C#:

class A{
   public void f(){}
}

//other file:
partial class A{
   public void g(){}
}

Now class A has both functions f and g.
In C++ however, once you define:

class A{
    public:
       void f();
}

f will become the only method in A. You can’t declare new methods in a new header file nor define methods that are not in the class definition in cpp files.