ConsoleColors.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleColors {
	class Program {
		static void Main(string[] args) {

			foreach(ConsoleColor colorA in Enum.GetValues(typeof(ConsoleColor))) {
				foreach(ConsoleColor colorB in Enum.GetValues(typeof(ConsoleColor))) {
					Console.BackgroundColor = colorA;
					Console.ForegroundColor = colorB;
					Console.Write('#');
				}
				Console.WriteLine();
			}
		}
	}
}