>Checking events in VBNet

>Due to some reason unknown to man the team behind VBNet decided that the developer should not be able to see if someone listened to your event or not. It is good in most cases but very bad in another.

In Csharp raising an event goes something like this:
var ev = MyEvent;
if( null != ev ){ ev( this, args ); }

Just look through the snippets (look in the context menu in the editor) and you will find the correct way to raise an event in Csharp.

VBNet on the other hand hides the if statement and the temporary variable from the developer. It is enough to write
RaiseEvent Me, args
and the event will be raise if there is someone listening – no need to check for null.

But what if you want to check if someone is listening. In my case I needed to know if the custom control was properly wired into the scaffolding of the application; the user control sometimes whished for more information and I had to know if someone was listening.
In Csharp this would have been easy with a check for null. But VBNet…

The solution is hidden. Just check the variable “MyEventEvent“. This means that your MyClick event has a hidden variable MyClickEvent that you can check for like this:
If MyClickEvent IsNot Nothing Then

I don’t like to use hidden and unoffical solutions but this is the only way I know of.

Honor those who should.

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