How to use events in C#?
In C#, events are a special type of delegate used to notify other objects of an action or a change in state. To use events, you first need to define an event and create an event handler to handle that event. Below are the basic steps for using events:
- Defining an event: Declare an event within a class, you can use the event keyword to define the event. For example:
public event EventHandler MyEvent;
- Create an event handler: Define a method to handle the event that must conform to the delegate’s signature. For example:
private void OnMyEvent(object sender, EventArgs e)
{
Console.WriteLine("MyEvent is raised");
}
- Associate events with event handlers: Use the += operator to add event handlers to events where they need to be triggered. For example:
MyEvent += OnMyEvent;
- Trigger the event: Trigger the event at the appropriate time by calling the event. For example:
MyEvent?.Invoke(this, EventArgs.Empty);
By following the above steps, you can use events in C# to facilitate communication between objects and notify of changes in their state.