Why is EventHandler TA useful generic type?

Why is EventHandler TA useful generic type?

The advantage of using EventHandler is that you do not need to code your own custom delegate if your event generates event data. You simply provide the type of the event data object as the generic parameter. The event handler is called whenever the event occurs, unless you remove the delegate.

What is C# EventHandler?

An event handler, in C#, is a method that contains the code that gets executed in response to a specific event that occurs in an application. Event handlers are used in graphical user interface (GUI) applications to handle events such as button clicks and menu selections, raised by controls in the user interface.

What is EventArgs C#?

EventArgs is also the class you use when an event does not have any data associated with it. When you create an event that is only meant to notify other classes that something happened and does not need to pass any data, include the EventArgs class as the second parameter in the delegate. You can pass the EventArgs.

Can event handler return a value?

Firing an event is a one-way signal. By default most event handlers return void , because single event may have several subscribers, and return value could become ambiguous. However, it is possible for handlers to return values. Simple delegates may have any return type.

When would you use generics in your code C#?

Generics overview

1. Use generic types to maximize code reuse, type safety, and performance.
2. The most common use of generics is to create collection classes.
3. The .
4. You can create your own generic interfaces, classes, methods, events, and delegates.

What is the return type of an event in net?

It depends on the type of the delegate you declare the event with. “Typical” events are declared with a delegate of type EventHandler or EventHandler which returns void , but nothing forbids declaring an event with a different type of delegate… if not the Principle Of Least Surprise (POLS).

What is generic delegates in C#?

Delegates defined within a generic class can use the generic class type parameters in the same way that class methods do. Generic delegates are especially useful in defining events based on the typical design pattern because the sender argument can be strongly typed and no longer has to be cast to and from Object.

How to use generic EventHandler in.net 2.0?

There is as of .NET 2.0 a generic EventHandler delegate type, which can be used to define an event in terms of the EventArgs type you wish to use, without having to create a redundant delegate type to use in the event declaration. Well, what about the EventArgs?

How to create an event handler in Java?

You simply provide the type of the event data object as the generic parameter. To associate the event with the method that will handle the event, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate.

What is the advantage of using EventHandler < teventargs >?

The advantage of using EventHandler is that you do not need to code your own custom delegate if your event generates event data. You simply provide the type of the event data object as the generic parameter. To associate the event with the method that will handle the event, add an instance of the delegate to the event.

Can you create a generic EventArgs class in FCL?

For passing a simple string or a number, this is simply too much boilerplate code. But we can create a generic EventArgs class, something that is missing in FCL and which will wrap our variable thus satisfying EventHandler .