This cannot be typed to Exception because it&#39;s possible to throw objects in .Net that do not derive from System.Exception.  This is not possible in C# or VB.Net but it is possible in other CLR based languages.  Hence the API must support this possibility and uses the type object.  

So while it shouldn&#39;t ever be null, it may not in fact be a System.Exception.

See CLI spec section 10.5 (specifically CLS rule 40) for more details

In addition to what Jared has already mentioned, you can safely cast to `Exception` in .NET Framework 2.0 and higher if `RuntimeCompatibilityAttribute(WrapNonExceptionThrows=true)` has been applied to your assembly (will be added automatically by the C# and VB compilers).  

When this attribute has been applied, non-Exception &quot;exceptions&quot; will be wrapped in `RuntimeWrappedException`.

I am working on dynamically creating some JavaScript that will be inserted into a web page as it&#39;s being constructed. 

The JavaScript will be used to populate a `listbox` based on the selection in another `listbox`. When the selection of one `listbox` is changed it will call a method name based on the selected value of the `listbox`.

For example:

`Listbox1` contains:

- `Colours`
- `Shapes`

If `Colours` is selected then it will call a `populate_Colours` method that populates another `listbox`.  
  
To clarify my question: How do I make that `populate_Colours` call in JavaScript?

How do I call a dynamically-named method in Javascript?

I have about 50 CGPoint objects that describe something like a &quot;path&quot;, and I want to add them to an NSArray. It&#39;s going to be a method that will just return the corresponding CGPoint for an given index. I don&#39;t want to create 50 variables like p1 = ...; p2 = ..., and so on. Is there an easy way that would let me to define those points &quot;instantly&quot; when initializing the NSArray with objects?


How can I add CGPoint objects to an NSArray the easy way?

Why is `UnhandledExceptionEventArgs.ExceptionObject` an object and not an `Exception`?

I am attaching to `AppDomain.UnhandledException`.

I would like to cast `UnhandledExceptionEventArgs.ExceptionObject` to an `Exception` and interogate it.

And with this in mind will it ever be null?

The [MSDN documentation][1] is not exatly useful.

&gt; Gets the unhandled exception object.




  [1]: http://msdn.microsoft.com/en-us/library/system.unhandledexceptioneventargs.exceptionobject.aspx

Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?

Why is <code>UnhandledExceptionEventArgs.ExceptionObject</code> an object and not an <code>Exception</code>?
I am attaching to <code>AppDomain.UnhandledException</code>.
I would like to cast <code>UnhandledExceptionEventArgs.ExceptionObject</code> to an <code>Exception</code> and interogate it.
And with this in mind will it ever be null?
The <a href="http://msdn.microsoft.com/en-us/library/system.unhandledexceptioneventargs.exceptionobject.aspx" target="_blank" rel="noopener noreferrer">MSDN documentation</a> is not exatly useful.
> Gets the unhandled exception object.

I have a Person object with a Nullable&lt;DateTime&gt; DateOfBirth property.  Is there a way to use LINQ to query a list of Person objects for the one with the earliest/smallest DateOfBirth value?

Here&#39;s what I started with:

```c#
var firstBornDate = People.Min(p =&gt; p.DateOfBirth.GetValueOrDefault(DateTime.MaxValue));
```

Null DateOfBirth values are set to DateTime.MaxValue in order to rule them out of the Min consideration (assuming at least one has a specified DOB).

But all that does for me is to set firstBornDate to a DateTime value.  What I&#39;d like to get is the Person object that matches that.  Do I need to write a second query like so:

```c#
var firstBorn = People.Single(p=&gt; (p.DateOfBirth ?? DateTime.MaxValue) == firstBornDate);
```

Or is there a leaner way of doing it?


How to use LINQ to select object with minimum or maximum property value

In C# 3.0, I&#39;m liking this style:

    // Write the numbers 1 thru 7
    foreach (int index in Enumerable.Range( 1, 7 ))
    {
    	Console.WriteLine(index);
    }

over the traditional `for` loop:

    // Write the numbers 1 thru 7
    for (int index = 1; index &lt;= 7; index++)
    {
    	Console.WriteLine( index );
    }

Assuming &#39;n&#39; is small so performance is not an issue, does anyone object to the new style over the traditional style?

Thoughts on foreach with Enumerable.Range vs traditional for loop

All of the Func&lt;T&gt; delegates return a value. What are the .NET delegates that can be used with methods that return void?

Func delegate with no return type

For those of you out there writing reusable components, what do you consider to be best practice if you&#39;re extending the functionality of the .NET framework?

For example, I&#39;m creating a Pop3 library at the moment as one doesn&#39;t exist in .NET. Do I create a custom namespace or do I use `System.Net.Mail` ?

namespace naming conventions

I have and old(ish) C# method I wrote that takes a number and converts it to any base:

    string ConvertToBase(int number, char[] baseChars);

It&#39;s not all that super speedy and neat. Is there a good, known way of achieving this in .NET?

I&#39;m looking for something that allows me to use &lt;b&gt;any&lt;/b&gt; base with an arbitrary string of characters to use.

This only allows bases 16, 10, 8 and 2:

    Convert.ToString(1, x);

I want to use this to achieve a massively high base taking advantage of numbers, all lower case and all upper case letters. Like in [this thread][1], but for C# not JavaScript.

Does anyone know of a good and efficient way of doing this in C#?


  [1]: https://stackoverflow.com/questions/656941/converting-decimals-to-sexagesimal-base-sixty-in-javascript

Quickest way to convert a base 10 number to any base in .NET?

I never did any serious Java coding before, but I learned the syntax, libraries, and concepts based on my existing skills (Delphi &amp; C#).  One thing I hardly understand is that I&#39;ve seen so much code that silently consume exceptions after `printStackTrace` like this:

        public void process() {
        	try {
        	    System.out.println(&quot;test&quot;);
        	} catch(Exception e) {
        	    e.printStackTrace();
            }
        }

There is similar code like this one in almost every Java article &amp; project I ran into. Based on my knowledge this is very bad. The exception should almost always be forwarded to the outer context like this:

        public void process() {
            try {
                System.out.println(&quot;test&quot;);
            } catch(Exception e) {
                e.printStackTrace();
    	        throw new AssertionError(e);
            }
        }

Most of the time the exception should end up being handled at the outermost loop which belongs to the underlying framework (Java Swing for example). Why does it look like the norm to code like this in the Java world? I&#39;m puzzled.

Based on my background, I&#39;d prefer to remove printStackTrace *entirely*. I would simply rethrow as an unhandled aka `RuntimeException` (or, even better, `AssertionError`), then catch and log it at the most appropriate place: the framework outermost loop.

        public void process() {
            try {
                System.out.println(&quot;test&quot;);
            } catch(Exception e) {
    	        throw new AssertionError(e);
            }
        }


Why do Java people frequently consume exceptions silently?

PHP prior to version 5.5 has no finally block - i.e., whereas in most sensible languages, you can do:

    try {
       //do something
    } catch(Exception ex) {
       //handle an error
    } finally {
       //clean up after yourself
    }

PHP has no notion of a finally block.  

Anyone have experience of solutions to this rather irritating hole in the language?
     

How can I get around the lack of a finally block in PHP?

Is there feature that will automatically break debugging on first exception occurrence?

So we 

 1. start application
 2. do something that throw exception
 3. got IntelliJ popped up highlighted line where exception occurred.

Is there &quot;Break on Exception&quot; in IntelliJ?

I am thinking of creating a debug tool for my Java application.

I am wondering if it is possible to get a stack trace, just like ``Exception.printStackTrace()`` but without actually throwing an exception?

My goal is to, in any given method, dump a stack to see who the method caller is.

Is there a way to dump a stack trace without throwing an exception in java?

What are some good patterns for error handling in VBA?

In particular, what should I do in this situation:

```lang-none
... some code ...
... some code where an error might occur ...
... some code ...
... some other code where a different error might occur ...
... some other code ...
... some code that must always be run (like a finally block) ...
```

I want to handle both errors, and resume execution after the code where the error may occur. Also, the finally code at the end must *always* run - no matter what exceptions are thrown earlier. How can I achieve this outcome?




What are some good patterns for VBA error handling?

I&#39;ve tried to use elmah with my asp.net site but whenever I try to go to http://localhost:port/elmah.axd I get resource not found exception. My web.config is given below.

        &lt;?xml version=&quot;1.0&quot;?&gt;
        &lt;configuration&gt;
          &lt;configSections&gt;
            &lt;sectionGroup name=&quot;elmah&quot;&gt;
              &lt;section name=&quot;security&quot; requirePermission=&quot;false&quot; 
                      type=&quot;Elmah.SecuritySectionHandler, Elmah&quot;/&gt;
              &lt;section name=&quot;errorLog&quot; requirePermission=&quot;false&quot; 
                      type=&quot;Elmah.ErrorLogSectionHandler, Elmah&quot; /&gt;
              &lt;section name=&quot;errorMail&quot; requirePermission=&quot;false&quot; 
                      type=&quot;Elmah.ErrorMailSectionHandler, Elmah&quot; /&gt;
              &lt;section name=&quot;errorFilter&quot; requirePermission=&quot;false&quot; 
                      type=&quot;Elmah.ErrorFilterSectionHandler, Elmah&quot;/&gt;
            &lt;/sectionGroup&gt;
          &lt;/configSections&gt;
          &lt;elmah&gt;
            &lt;security allowRemoteAccess=&quot;0&quot; /&gt;
            &lt;errorLog type=&quot;Elmah.SqlErrorLog, Elmah&quot; 
                     connectionStringName=&quot;elmah-sql&quot; /&gt;
            &lt;errorMail
                    from=&quot;my@account&quot;
                    to=&quot;myself&quot;
                    subject=&quot;ERROR From Elmah:&quot;
                    async=&quot;true&quot;
                    smtpPort=&quot;587&quot;
                    smtpServer=&quot;smtp.gmail.com&quot;
                    userName=&quot;my@account&quot;
                    password=&quot;mypassword&quot; /&gt;
          &lt;/elmah&gt;

          &lt;connectionStrings&gt;
            &lt;add name=&quot;elmah-sql&quot; connectionString=&quot;data source=(sqlserver); 
                   database=elmahdb;
                 integrated security=false;User ID=user;Password=password&quot;/&gt;
          &lt;/connectionStrings&gt;
          &lt;system.web&gt;
            &lt;compilation debug=&quot;true&quot;&gt;
              &lt;assemblies&gt;
                &lt;add assembly=&quot;Elmah, Version=1.0.10617.0, Culture=neutral, 
                   PublicKeyToken=null&quot;/&gt;
              &lt;/assemblies&gt;
            &lt;/compilation&gt;
            &lt;authentication mode=&quot;Windows&quot;/&gt;

            &lt;httpHandlers&gt;
              &lt;remove verb=&quot;*&quot; path=&quot;*.asmx&quot;/&gt;
              &lt;add verb=&quot;*&quot; path=&quot;*.asmx&quot; validate=&quot;false&quot; 
                type=&quot;System.Web.Script.Services.ScriptHandlerFactory, 
                   System.Web.Extensions, Version=3.5.0.0, Culture=neutral, 
                      PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add verb=&quot;*&quot; path=&quot;*_AppService.axd&quot; validate=&quot;false&quot; 
                   type=&quot;System.Web.Script.Services.ScriptHandlerFactory, 
                   System.Web.Extensions, Version=3.5.0.0, Culture=neutral, 
                       PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add verb=&quot;GET,HEAD&quot; path=&quot;ScriptResource.axd&quot; 
                     type=&quot;System.Web.Handlers.ScriptResourceHandler, 
                   System.Web.Extensions, Version=3.5.0.0, Culture=neutral, 
                        PublicKeyToken=31BF3856AD364E35&quot; validate=&quot;false&quot;/&gt;
            &lt;/httpHandlers&gt;
            &lt;httpModules&gt;
              &lt;add name=&quot;ScriptModule&quot; type=&quot;System.Web.Handlers.ScriptModule, 
                    System.Web.Extensions, Version=3.5.0.0, Culture=neutral, 
                    PublicKeyToken=31BF3856AD364E35&quot;/&gt;
            &lt;/httpModules&gt;
          &lt;/system.web&gt;

          &lt;system.webServer&gt;
            &lt;validation validateIntegratedModeConfiguration=&quot;false&quot;/&gt;
            &lt;modules runAllManagedModulesForAllRequests=&quot;true&quot;&gt;
              &lt;remove name=&quot;ScriptModule&quot;/&gt;
              &lt;add name=&quot;ScriptModule&quot; preCondition=&quot;managedHandler&quot; 
                    type=&quot;System.Web.Handlers.ScriptModule, 
                   System.Web.Extensions, Version=3.5.0.0, Culture=neutral, 
                     PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add name=&quot;ErrorMail&quot; type=&quot;Elmah.ErrorMailModule, Elmah&quot;/&gt;
              &lt;add name=&quot;ErrorLog&quot; type=&quot;Elmah.ErrorLogModule, Elmah&quot;/&gt;
              &lt;add name=&quot;ErrorFilter&quot; type=&quot;Elmah.ErrorFilterModule, Elmah&quot;/&gt;
            &lt;/modules&gt;

            &lt;handlers&gt;
              &lt;remove name=&quot;WebServiceHandlerFactory-Integrated&quot;/&gt;
              &lt;remove name=&quot;ScriptHandlerFactory&quot;/&gt;
              &lt;remove name=&quot;ScriptHandlerFactoryAppServices&quot;/&gt;
              &lt;remove name=&quot;ScriptResource&quot;/&gt;
              &lt;add name=&quot;ScriptHandlerFactory&quot; verb=&quot;*&quot; path=&quot;*.asmx&quot; 
                    preCondition=&quot;integratedMode&quot; 
                   type=&quot;System.Web.Script.Services.ScriptHandlerFactory, 
                        System.Web.Extensions, Version=3.5.0.0, 
                   Culture=neutral, PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add name=&quot;ScriptHandlerFactoryAppServices&quot; verb=&quot;*&quot; 
                path=&quot;*_AppService.axd&quot; preCondition=&quot;integratedMode&quot; 
                   type=&quot;System.Web.Script.Services.ScriptHandlerFactory, 
                     System.Web.Extensions, Version=3.5.0.0, 
                   Culture=neutral, PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add name=&quot;ScriptResource&quot; preCondition=&quot;integratedMode&quot; 
                verb=&quot;GET,HEAD&quot; path=&quot;ScriptResource.axd&quot; 
                   type=&quot;System.Web.Handlers.ScriptResourceHandler, 
                System.Web.Extensions, Version=3.5.0.0, 
                   Culture=neutral, PublicKeyToken=31BF3856AD364E35&quot;/&gt;
              &lt;add name=&quot;Elmah&quot; verb=&quot;POST,GET,HEAD&quot; path=&quot;elmah.axd&quot; 
                           preCondition=&quot;integratedMode&quot; 
                   type=&quot;Elmah.ErrorLogPageFactory, Elmah&quot;/&gt;
            &lt;/handlers&gt;
          &lt;/system.webServer&gt;
        &lt;/configuration&gt;

EDIT: Elmah = (Error Logging Modules and Handlers)  
http://code.google.com/p/elmah/

Elmah not working with asp.net site

I ask because I couldn&#39;t find the stack trace in Visual Studio, while debugging an exception that occurred.


How do I find the stack trace in Visual Studio?

In Java, is there any way to get(catch) all `exceptions` instead of catch the exception individually?

How can I catch all the exceptions that will be thrown through reading and writing a file?

I see that the `Finally` in `Try .. Catch` will always execute after any parts of the execution of the try catch block.
 
Is it any different to just skip the `Finally` section and just run it after, outside the try catch block?

Example 1, Try ... Catch ... Finally ... End Try
----------------------------------------

        Try
            &#39;Do something
        Catch ex As Exception
            &#39;Handle exception
        Finally
            &#39;Do cleanup
        End Try

Example 2, Try ... Catch ... End Try ... Do the finally stuff outside
----------------------------------------


        Try
            &#39;Do something
        Catch ex As Exception
            &#39;Handle exception
        End Try
        &#39;Do cleanup


Why use Finally in Try ... Catch

I have a small WinForms app that utilizes a BackgroundWorker object to perform a long-running operation.

The background operation throws occasional exceptions, typically when somebody has a file open that is being recreated.

Regardless of whether the code is run from the IDE or not .NET pops up an error dialog informing the user that an Unhandled exception has occurred.  Compiling the code using the Release configuration doesn&#39;t change this either.

According to [MSDN][1]:
 
&gt; If the operation raises an exception that your code does not handle, the BackgroundWorker catches the exception and passes it into the RunWorkerCompleted event handler, where it is exposed as the Error property of System.ComponentModel..::.RunWorkerCompletedEventArgs. If you are running under the Visual Studio debugger, the debugger will break at the point in the DoWork event handler where the unhandled exception was raised.

I expect these exceptions to be thrown on occasion and would like to handle them in the RunWorkerCompleted event rather than in DoWork.  My code works properly and the error is handled correctly within the RunWorkerCompleted event but I can&#39;t for the life of me figure out how to stop the .NET error dialog complaining about the &quot;Unhandled exception&quot; from occurring.

Isn&#39;t the BackgroundWorker supposed to catch that error automagically?  Isn&#39;t that what the MSDN documentation states?  What do I need to do to inform .NET that this error *is* being handled while still allowing the exception to propage into the Error property of RunWorkerCompletedEventArgs?

  [1]: http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.dowork.aspx &quot;MSDN&quot;

Unhandled exceptions in BackgroundWorker

    protected override void OnStart(string[] args)
    {
    	AppDomain.CurrentDomain.UnhandledException +=
            new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
    
        Thread.Sleep(10000);
    
    	throw new Exception();
    }
    
    void CurrentDomain_UnhandledException(object sender,
                                          UnhandledExceptionEventArgs e)
    {
    }

I attached a debugger to the above code in my windows service, setting a breakpoint in CurrentDomain_UnhandledException, but it was never hit. The exception pops up saying that it is unhandled, and then the service stops. I even tried putting some code in the event handler, in case it was getting optimized away.

Is this not the proper way to set up unhandled exception handling in a windows service?

How can I set up .NET UnhandledException handling in a Windows service?

Up until now, I just put a try/catch block around the `Application.Run` in the `Program.cs` entry point to the program. This catches all exceptions well enough in Debug mode, but when I run the program without the debug mode, exceptions don&#39;t get handled anymore. I get the unhandled exception box.

I don&#39;t want this to happen. I want all exceptions to be caught when running in non-debug mode. The program has multiple threads and preferably all exceptions from them get caught by the same handler; I want to log exceptions in the DB. Does anyone have any advice in how to do this?


How can I make something that catches all &#39;unhandled&#39; exceptions in a WinForms application?

    class throwseg1
    {
        void show() throws Exception
        {
            throw new Exception(&quot;my.own.Exception&quot;);
        }

        void show2() throws Exception  // Why throws is necessary here ?
        {
            show();
        }

        void show3() throws Exception  // Why throws is necessary here ?
        {
            show2();
        }
    
        public static void main(String s[]) throws Exception  // Why throws is necessary here ?
        {
            throwseg1 o1 = new throwseg1();
            o1.show3();
        }
    }

Why compiler reports that methods `show2()`, `show3()`, and `main()` have 

&gt; unreported exception Exception that must be caught or declared to be thrown

when I remove `throws Exception` from these methods? 

Why is &quot;throws Exception&quot; necessary when calling a function?

How do I catch _all_ unhandled exceptions that occur in ASP.NET Web Api so that I can log them?

So far I have tried:

* Create and register an [`ExceptionHandlingAttribute`](http://weblogs.asp.net/fredriknormen/archive/2012/06/11/asp-net-web-api-exception-handling.aspx)
* Implement an `Application_Error` method in `Global.asax.cs`
* Subscribe to `AppDomain.CurrentDomain.UnhandledException`
* Subscribe to `TaskScheduler.UnobservedTaskException`

The `ExceptionHandlingAttribute` successfully handles exceptions that are thrown within controller action methods and action filters, but other exceptions are not handled, for example:

* Exceptions thrown when an `IQueryable` returned by an action method fails to execute
* Exceptions thrown by a message handler (i.e. `HttpConfiguration.MessageHandlers`)
* Exceptions thrown when creating a controller instance

Basically, if an exception is going to cause a 500 Internal Server Error to be returned to the client, I want it logged. Implementing `Application_Error` did this job well in Web Forms and MVC - what can I use in Web Api?

Content Type	Original Author	Original Content on Stackoverflow
Question	Simon	View Question on Stackoverflow
Solution 1 - .Net	JaredPar	View Answer on Stackoverflow
Solution 2 - .Net	Nicole Calinoiu	View Answer on Stackoverflow

Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?

.Net Problem Overview

.Net Solutions

Solution 1 - .Net

Solution 2 - .Net

How can I add CGPoint objects to an NSArray the easy way?

How do I call a dynamically-named method in Javascript?

Attributions