C#中自定义异常

using System;

public class DataHouse

{

    public static void FindData( long ID) 

    {

        if( ID>0 && ID<1000)

            Console.WriteLine( ID );

        else

            throw new DataHouseException("已到文件尾");

    }

}

public class BankATM 

{

    public static void GetBalanceInfo( long  ID) 

    {

        try 

        {

            DataHouse.FindData(ID);

        }

        catch (DataHouseException e) 

        {

            throw new MyAppException("账号不存在",e);

        }

    }

}

public class DataHouseException:ApplicationException 

{

    public DataHouseException( string message )

        :base(message)

    {}

}

public class MyAppException:ApplicationException 

{

    public MyAppException (string message) 

        : base (message) 

    {}

    public MyAppException (string message, Exception inner)

        : base(message,inner)

    {}   

}

public class Test 

{

    public static void Main() 

    {

        try 

        {

            BankATM.GetBalanceInfo( 12345L);

        }

        catch(Exception e) 

        {

            Console.WriteLine ("出现了异常： {0}", e.Message);

            Console.WriteLine ("内部原因： {0}",e.InnerException.Message);

        }

    }

}