using System;

using System.Net.Http;

public class Program

{

    public static void Main()

    {

        var baseUri = new Uri("https://test.com");

        var name = "name";

        var newUri = new Uri(baseUri, name);

        Console.WriteLine($"Relative path is NOT null: {newUri}");

        name = null;

        newUri = new Uri(baseUri, name);

        Console.WriteLine($"Relative path IS null: {newUri}");

    }

}