Exception throwing

In C#, will the folloing code throw e containin开发者_如何学Gog the additional information up the call stack?

...
catch(Exception e)
{
  e.Data.Add("Additional information","blah blah");
  throw;
}

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Yes, it will. A lot of developers don't realise that the following code will throw a new exception from that point in the call-stack, not the calls made previously up the stack before the catch.

...
catch(Exception e)
{
  e.Data.Add("Additional information","blah blah");
  throw e;
}

I learnt this the hard way!

---

        var answer = "No";
        try
        {
            try
            {
                throw new Exception();
            }
            catch (Exception e)
            {
                e.Data.Add("mykey", "myvalue");
                throw;
            }
        }
        catch (Exception e)
        {
            if((string)e.Data["mykey"] == "myvalue")
                answer = "Yes";
        }

        Console.WriteLine(answer);
        Console.ReadLine();     

When you run the code you will find that the answer is yes :-)

---

Exceptions are not immutable, and being able to add information to them is one reason for this.

So, yes, the data will be added to the exception information bubbling up.

---

You can do this but due to FxCop I've always created custom exceptions when ever I throw and exception. This gives the caller the ability to easily catch and understand different types of errors. If you need to include a subsequent exception you can use the InnerException of Exception or simply ad a member variable for your new Exception.

This tells you how to make you own successfully. http://blog.gurock.com/articles/creating-custom-exceptions-in-dotnet/

This is one of those programming things that people like to skip because it simply extra work to get an application functional.

This is a page from my personal Zen of Programming:

Your program is your house. Make it as nice as you can so it's easy and fun to live in.