C#练习

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
//重复让用户输入输入一个数，判断该数是否质数，当输入“q”时，程序运行结束！（质数的判断要求用方法来实现）。
namespace 平时练习
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("please input a num:");
            string numberstring = Console.ReadLine();
            while (numberstring != "q")
            {
                int numint = Convert.ToInt32(numberstring);
                bool result = Panduan(numint);
                if (result == true)
                    Console.WriteLine("{0}is zhishu", numint);
                else
                    Console.WriteLine("{0} is not zhishu",numint);
                Console.WriteLine("please input a num:");
                numberstring= Console.ReadLine();
                Console.ReadKey();
            }

        }

        private static bool Panduan(int numint)
        {
            bool result = true;
            double x = Math.Sqrt(numint);
            for (int i = 2; i <= x;i ++ )
            {
                if (numint % i == 0)
                {
                    result = false; break;
                }
            }
            return result;
        }
    }
}