如何处理.NET中的DivideByZeroException示例

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

namespace Dividebyzero

{

    class Program

    {

      static  int N1, N2, N3;

      public static int div(int a,int b)

      {

          if (b <= 0)

          {

              //抛出异常

              throw new DivideByZeroException("b不能为0 ");

          }
          else{
          	return Convert.ToInt32(a/b);
          }

      }

        static void Main(string[] args)

        {

            try

            {

                N1= 3;
                N2=0;
                N3 = div(N1,N2);

                Console.WriteLine("Result is {0}", N3);

            }

             catch (DivideByZeroException ex)

            {

                Console.WriteLine("Division by Zero occurs" + ex);

                Console.WriteLine("HelpLink = {0}", ex.HelpLink);

                Console.WriteLine("Message = {0}", ex.Message);

                Console.WriteLine("Source = {0}", ex.Source);

                Console.WriteLine("StackTrace = {0}", ex.StackTrace);

                Console.WriteLine("TargetSite = {0}", ex.TargetSite);

            }

            finally

            {

               Console.WriteLine("finally块总是会被执行");

               Console.ReadLine();

            }

        }

    }

}

如果在除法中除数是0，那么会抛出DivideByZeroException异常。