Should DispatchEvent be the last statement of a function?

问题

Should dispatchEvent must be the last statement of any function ?

回答1:

When you call dispatchEvent, all handlers for that event are immediately called before the rest of the function body where dispatchEvent was called runs. Does that mean that you need to call dispatchEvent as the last thing in a function body? Only if the code that is after the dispatchEvent call somehow depends on something that will be adversely changed when the handlers run.

回答2:

Absolutely not， dispatchEvent() can be invoked at anywhere as you wish. What make you to ask this question?

回答3:

Nope

dispatchEvent will fire an event, and the corresponding event handler will be executed immediately after the dispatchEvent is invoked.

However, unlike a return, the remaining lines of code will be executed after the event handler is completely executed

Simple test:

//Movie clip (mClip1)

function buzz():void {
    trace("buzz:1");
    dispatchEvent(new Event("justAnotherEvent"));
    trace("buzz:2");
}


//on the stage,

mClip1.addEventListener("justAnotherEvent", ping);

function ping(e:Event):void {
    trace("ping");
}

Output:

buzz:1
ping
buzz:2

edit I KNOW that using a literal string instead of a const for the event type is a bad practice, but as I said, this is just a simple quick down and dirty test.

来源：https://stackoverflow.com/questions/8270725/should-dispatchevent-be-the-last-statement-of-a-function