C#上手练习2（while、do while语句）

using System;

namespace KingTest03
{
    class Program
    {
        static void Main(string[] args)
        {
            Program program = new Program();
            program.Sum1();
            Console.WriteLine();
            Console.WriteLine("while和Do While的区别如下");
            program.while1();
            program.while2();
        }
        public void Sum1()//计算1到100的和
        {
            int a1 = 1;
            int sum1 = 0;
            while (a1 <= 100)
            {
                if (a1 < 100)
                {
                    sum1 = sum1 + a1;
                    Console.Write(a1 + "+");
                    a1++;
                }
                else
                {
                    sum1 = sum1 + a1;
                    Console.Write(a1 + "=");
                    a1++;
                }
            }
            Console.Write(sum1);
        }
        public void while1()//先去判断条件，再执行表达式
        {
            Console.WriteLine("请输入一个整数");
            int i = int.Parse(Console.ReadLine());
            int j = 1;
            while (i < j)
            {
                Console.WriteLine(i);
                break;
            }
        }
        public void while2()//先执行表达式，再去判断条件
        {
            Console.WriteLine("请输入一个整数");
            int i = int.Parse(Console.ReadLine());
            int j = 1;
            do
            {
                Console.WriteLine(i);
                break;
            } while (i < j);
        }
    }
}