当我实例化一个派生类时,我如何防止调用基础构造函数？

using System;

namespace TestConstru22323
{
    class Program
    {
        static void Main(string[] args)
        {
            Customer customer = new Customer("Jim","Smith");
            Customer c = new Customer();
            Console.WriteLine(customer.Display());

            Console.ReadLine();
        }
    }

    public class Person
    {
        public Person()
        {
            Console.WriteLine("I don't always want this constructor to be called. I want to call it explicitly.");
        }
    }

    public class Customer : Person
    {
        private string _firstName;
        private string _lastName;

        //public Customer(string firstName,string lastName): base()  //this explicitly calls base empty constructor
        public Customer(string firstName,string lastName) //but this calls it anyway,why?
        {
            _firstName = firstName;
            _lastName = lastName;
        }

        public string Display()
        {
            return String.Format("{0},{1}",_lastName,_firstName);
        }
    }
}