How to find keyword in Microsoft Technologies

Question

I am creating parser algorithm and i want to know on what basis Microsoft is deciding whether word is keyword. Example: if in a sentence word is noun than that it is keyword.

Consider following example text content

Hi,

I have a base class which contains 4 methods.

Class BaseClass

{

Public void A(){}

Public void B(){}

public void c{}

public void d{}

}

I have two clients like ClientA and ClientB.

Now I want ,ClientA can access two methods A and D and ClientB can access two methods B and C.

How to solve this problem ?. What are the best approach to achieve this?

Can anyone please help me to find keywords in any given content using C# language.