C#编程基础 实验（7） (1-2)

1.将百分制转换成五分制，如果输入的百分制成绩超出0~100时，程序抛出异常。

代码如下：

using System;
using System.Collections;
using System.Collections.Generic;
namespace Program
{
class OverflowRange : ApplicationException
{
public OverflowRange(string msg):base(msg)
{ }
}
class Program
{

static void Main(string[] args)
{
try
{
Console.Write("输入一个百分数：");
int num = Convert.ToInt32(Console.ReadLine());
if (num < 0 || num > 100)
{
throw new OverflowRange("数值不在0~100之间");
}
double result = (double)num * 5.0 / 100;
Console.WriteLine("转换成五分制为：{0}", result);
}
catch (FormatException)
{
Console.WriteLine("必须输入数字");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
finally
{
Console.ReadKey();
}
}
}

}

2.编写一个计算阶乘的程序，当输入的数据是带小数时，引发异常。

using System;
using System.Collections;
using System.Collections.Generic;
namespace Program
{
class WithoutDecimal : ApplicationException
{
public WithoutDecimal(string msg):base(msg)
{ }
}
class Program
{

static void Main(string[] args)
{
try
{
Console.Write("输入一个数：");
double num = Convert.ToDouble(Console.ReadLine());
if (num - (int)num != 0)
{
throw new WithoutDecimal("输入的数据带小数");
}
int sum = 1;
for (int i = 2; i <= (int)num; i++)
{
sum *= i;
}
Console.WriteLine("{0}的阶乘为{1}", num, sum);
}
catch (FormatException)
{
Console.WriteLine("必须输入数字");
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
finally
{
Console.ReadKey();
}
}
}

}