C#

George_George wrote:

In the C# compiler expanded code, no catch block? Just a finally block?

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Xml;

class Test
{

    class MyException : ApplicationException
    {
        public MyException (string message)
            : base(message)
        {

        }
    }

    class MyObject : IDisposable
    {
        public virtual void Dispose()
        {
            Console.WriteLine("Disposed ");
            throw new MyException("Disposed exception. ");
        }

    }

    public static void Main()
    {
        try
        {
            using (MyObject myobj = new MyObject())
            {
                throw new MyException("Hello World");
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
    }
}

try
        {
            MyObject myobj = new MyObject();
            try
            {
                throw new MyException("Hello World");
            }
            finally
            {
                myobj.Dispose();
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }

George_George wrote:

It is in theory that the information of MyException("Hello World") is missing when there is exception in Dispose, right?

George_George wrote:

when there is exception and we are in finally block because of the exception

George_George wrote:

How can you write a common finally block, to handle exception at first, then Dispose?

public static void Main()
    {
        try
        {
            using (MyObject myobj = new MyObject())
            {
                try{
                   throw new MyException("Hello World");
                }
                catch(MyException)
                {
                     
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.ToString());
        }
    }

John Simmons / outlaw programmer wrote:

So which is it - a good thing, or a bad thing?

John Simmons / outlaw programmer wrote:

automatic-ness of memory handling

John Simmons / outlaw programmer wrote:

Personally, I avoid "using" statements because I think they obfuscate the intent of code.

S. Senthil Kumar wrote:

Really? How else do you close DB connections or file streams?

George_George wrote:

If there is exception, and in both exception handler and finally block, I do not call Close/Dispose explicitly, will Dispose/Close be called automatically during exception

Vikram A Punathambekar wrote:

No. Unless, of course, the control comes out of the using block before the exception is caught. Why don't you try it and see? (Just put a Console.WriteLine in the Dispose block and another in the finally block.)