C#_switch语句，for循环，do while循环,while循环

1:switch语句，代码如下：

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

namespace ConsoleApplication33
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("请输入分数：");
            int score = int.Parse(Console.ReadLine());
            Console.WriteLine("得分是：");
            switch (score / 10)
            {
                case 10:
                case 9:
                    Console.WriteLine("A");
                    break;
                case 8:
                    Console.WriteLine("B");
                    break;
                case 7:
                    Console.WriteLine("C");
                    break;
                case 6:
                    Console.WriteLine("D");
                    break;
                default:
                    Console.WriteLine("E");
                    break;
            }
        }
    }
}

　运行结果：

2：for循环，代码如下：

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

namespace ConsoleApplication34
{
    class Program
    {
        static void Main(string[] args)
        {
            int i;
            int sum = 0;
            for (i = 0; i <= 100; i++)
            {
                sum += i;
            }
            Console.WriteLine("最终结果是：{0}",sum);
        }
    }
}

　运算结果：

 3：do while语句，代码如下：

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

namespace ConsoleApplication35
{
    class Program
    {
        static void Main(string[] args)
        {
            int i = 0;
            int sum = 0;
            do
            {
                sum += i;
                i++;
            } while (i <= 100);
            Console.WriteLine("最终结果是：{0}", sum);
        }
    }
}

　　运行结果：

4：while循环，代码如下：

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

namespace ConsoleApplication36
{
    class Program
    {
        static void Main(string[] args)
        {
            int i = 0;
            int sum = 0;
            while(i<=100)
            {
                sum += i;
                i++;
            } 
            Console.WriteLine("最终结果是：{0}", sum);
        }
    }
}

　　运行结果一样。

 5：下面来一个综合的例子，为多名职员计算缴税金额。代码如下：

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

namespace ConsoleApplication37
{
    class Program
    {
        static void Main(string[] args)
        {
            decimal sal;
            decimal salary;
            decimal tax;
            int count = 0;//记录处理数据个数
            char ch;//记录用户输入的字符
            do
            {
                Console.Write(++count);
                Console.Write("请输入职员工资：");
                salary = Convert.ToDecimal(Console.ReadLine());//输入职员工资
                sal = salary - 3500;
                if (sal <= 0m)
                    tax = 0m;//decimal类型要加后缀m
                else if (sal <= 1500m)
                    tax = sal * 0.03m;
                else if (sal <= 4500m)
                    tax = sal * 0.1m-105;
                else if (sal <= 9000m)
                    tax = sal * 0.2m-555;
                else if (sal <= 35000m)
                    tax = sal * 0.25m-1005;
                else if (sal <= 55000m)
                    tax = sal * 0.3m-2755;
                else if (sal <= 80000m)
                    tax = sal * 0.35m-5505;
                else
                    tax = sal * 0.45m-13505;
                Console.WriteLine("应交税金为：" + tax.ToString());
                Console.Write("继续吗？");
                ch = Convert.ToChar(Console.ReadLine());//用户输入字符
                //若用户输入的是除大小写Y或大小写N以外的其他字符，则要求用户重新输入
                while (ch != 'Y' && ch != 'y' && ch !='N' && ch != 'n')
                {
                    Console.WriteLine("对不起！只允许大小写Y或大小写N！
继续吗？");
                    ch = Convert.ToChar(Console.ReadLine());
                }
            }
            while (ch == 'Y'||ch == 'y');

            Console.WriteLine("谢谢使用！");
            Console.ReadLine();

        }
    }
}

　　运行结果：