Global Exception Handling for winforms control

Question

When working on ASP.NET 1.1 projects I always used the Global.asax to catch all errors. I'm looking for a similar way to catch all exceptions in a Windows Forms user control, which ends up being a hosted IE control. What is the proper way to go about doing something like this?

Answer 1

You need to handle the System.Windows.Forms.Application.ThreadException event for Windows Forms. This article really helped me: http://bytes.com/forum/thread236199.html.

Answer 2

To Handle Exceptions Globally...

Windows Application

System.Windows.Forms.Application.ThreadException event

Generally Used in Main Method. Refer MSDN Thread Exception

Asp.Net

System.Web.HttpApplication.Error event

Normally Used in Global.asax file. Refer MSDN Global.asax Global Handlers

Console Application

System.AppDomain.UnhandledException event

Generally used in Main Method. Refer MSDN UnhandledException

Answer 3

If you're using VB.NET, you can tap into the very convenient ApplicationEvents.vb. This file comes for free with a VB.NET WinForms project and contains a method for handling unhandled exceptions.

To get to this nifty file, it's "Project Properties >> Application >> Application Events"

If you're not using VB.NET, then yeah, it's handling Application.ThreadException.

Answer 4

Currently in my winforms app I have handlers for Application.ThreadException, as above, but also AppDomain.CurrentDomain.UnhandledException

Most exceptions arrive via the ThreadException handler, but the AppDomain one has also caught a few in my experience

Answer 5

Code from MSDN: http://msdn.microsoft.com/en-us/library/system.appdomain.unhandledexception.aspx?cs-save-lang=1&cs-lang=vb#code-snippet-2

Sub Main()
  Dim currentDomain As AppDomain = AppDomain.CurrentDomain
  AddHandler currentDomain.UnhandledException, AddressOf MyHandler

  Try 
     Throw New Exception("1")
  Catch e As Exception
     Console.WriteLine("Catch clause caught : " + e.Message)
     Console.WriteLine()
  End Try 

  Throw New Exception("2")
End Sub 

Sub MyHandler(sender As Object, args As UnhandledExceptionEventArgs)
  Dim e As Exception = DirectCast(args.ExceptionObject, Exception)
  Console.WriteLine("MyHandler caught : " + e.Message)
  Console.WriteLine("Runtime terminating: {0}", args.IsTerminating)
End Sub