How to make a program server answer domain name from client.

Question

I have make a program in windows form C# about server answer domain name of client videlicet that if client send a hostname or username to server the server will reply a IP address of client are you understand my question ?  I need a document or source code to referencethank very much

Maria Bili · Answer

The required of my homwork is: write a program server answer domain name of client when client send hostname (client's name) server will return (reply) client Ip Address (list of hostname and Ip student home -made to demo) sorry that my ability english of mine is not good are you understand ? so who have a example or guide please instruction me. thank.

Maria Bili · Answer

who known? please give me a intruction or guide ? I need an example about it?