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

namespace BigPower
{
    class Program
    {
        static void Main(string[] args)
        {
            int d = 9;
            Console.WriteLine(Convert.ToString(d, 2));

            Console.WriteLine(TestBit(d, 0));
            Console.WriteLine(TestBit(d, 1));
            Console.WriteLine(TestBit(d, 2));
            Console.WriteLine(TestBit(d, 3));

            Console.Read();
        }

        // 判断整数的第i位置是否为1 (i从0开始)
        public static bool TestBit(int d, int i)
        {
            int b = (d >> i) & 1;
            return b == 1;
        }
    }
}

运行效果