Throw

13y2kVisual Basic .NET

http://www.c-sharpcorner.com/UploadFile/akkiraju/difference-between-throw-exception-and-throw-clause/

Program is given in the above website. In the 1st example the output is not coming like as shown I don't know why it may be due to the different version of VS express. Not only that how trace is in the output without StackTrace is in code.

System.Exception was unhandled
Message=Original Exception occurred in ExceptionMethod
Source=TestingThrowExceptions
StackTrace:
at TestingThrowExceptions.Program.Main(String[] args) in C:\TestProjects\TestingThrowExceptions\TestingThrowExceptions\Program.cs:line 26

7 Replies

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13y ago
Thank you for your help.
Vulpes13y ago
In addition to its uses in arithmetic, the += operator is also used to add a handler to an event or delegate's invocation list (-= is to used to remove it).

In this case we're adding the handler, My Handler, to the invocation list of the AppDomain.UnhandledException event so that, when this event fires, the handler will be called automatically.

See this link for details of this event which provides notifications for otherwise uncaught exceptions:

http://msdn.microsoft.com/en-us/library/system.appdomain.unhandledexception.aspx

As this is a special use of the += operator, there's no other way to write the code.
13y ago
I am not familiar with following code.

currentDomain.UnhandledException += new UnhandledExceptionEventHandler(MyHandler);

x +=1 is in more detail expression can be written as x = x + 1. I wish to know is there any similar way to write the above code.
Vulpes13y ago
Maha,

I don't use VS 2012 Express (I prefer the 2010 edition) but apparently the Exception Assistant (as it was called) has been removed from the Express edition and you now need the Pro (or better) edition to use it. See this SO thread:

http://stackoverflow.com/questions/14542831/how-to-view-exception-details-in-visual-studio-express

However, you should be able to see what Akkiraju was talking about (the exception details will now be printed to the console) if you add the highlighted code to the program and press Ctrl + F5 to Start without debugging.

Notice that line 26 will now become 29:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TestingThrowExceptions
{
class Program
{
public void ExceptionMethod()
{
throw new Exception("Original Exception occurred in ExceptionMethod");

}

static void Main(string[] args)
{
AppDomain currentDomain = AppDomain.CurrentDomain;
currentDomain.UnhandledException += new UnhandledExceptionEventHandler(MyHandler);

Program p = new Program();
try
{
p.ExceptionMethod();
}
catch (Exception ex)
{

throw;
}
}
static void MyHandler(object sender, UnhandledExceptionEventArgs args)
{
Exception e = (Exception)args.ExceptionObject;
Console.WriteLine("Message = {0}", e.Message);
Console.WriteLine("Source = {0}", e.Source);
Console.WriteLine("StackTrace :");
Console.WriteLine(e.StackTrace);
Console.ReadKey();
}

}
}
Rajesh B13y ago
http://www.c-sharpcorner.com/Forums/Thread/222551/ pls go through this thread and solve my issue there i have given every details regarding this in comments. so pls go through this
13y ago
Image of the pops up box is attached. I couldn't see anything you said. It is VS Express 2012.
Vulpes13y ago
To see the stack trace, when the Exception box pops up, click on 'Copy exception detail to the clipboard' under Actions at the bottom of the box.

Now fire up Notepad and paste the contents of the clipboard into it.

You should find that the stack trace details are similar to what Akkiraju said they would be.