using System;
using System.Collections.Generic;
using System.Linq;
 
public class Employee
{
	public int Id {get; set;}
	public string FirstName { get; set;}
	public string LastName {get; set;}
}
 
public class Test
{
	private static string[] GetColumnValues(Employee emp, params int[] cols)
	{
		var props = emp.GetType().GetProperties();
		var values = new List<string>();
		foreach(var i in cols)
		{
			if (i >= 0 && i < props.Length)
			{
				object value = props[i].GetValue(emp, null);
				values.Add(value == null ? string.Empty : value.ToString());
			}
		}
		return values.ToArray();
	}
	public static void Main()
	{
	    var emp = new Employee() { Id = 1, FirstName = "John", LastName = "Smith" };
	    var values = GetColumnValues(emp, 0, 2);
	    Console.WriteLine(string.Join("\t", values));
	}
}