Calling C# events from outside the owning class?

Question

Is it possible under any set of circumstances to be able to accomplish this?

My current circumstances are this:

public class CustomForm : Form
{
             


        

Answer 1

The event keyword in c# modifies the declaration of the delegate. It prevents direct assignment to the delegate (you can only use += and -= on an event), and it prevents invocation of the delegate from outside the class.

So you could alter your code to look like this:

public class CustomGUIElement
{
...
    public MouseEventHandler Click;
    // etc, and so forth.
...
}

Then you can invoke the event from outside the class like this.

myCustomGUIElement.Click(sender,args);

The drawback is that code using the class can overwrite any registered handlers very easily with code like this:

myCustomGUIElement.Click = null;

which is not allowed if the Click delegate is declared as an event.