as3布爾變量不會超出函數范圍

Question

由於某種原因，我的值未在函數外部進行更新。 我試圖制作一個按鈕，例如“加號”，將影片剪輯“ topArrow”不斷向上移動。 我認為布爾值將是觸發此操作的簡便方法，但不會在函數外部進行更新。 為什么是這樣？

import flash.events.Event;
import flash.events.MouseEvent;

var speed:Number = 1;

plus.addEventListener(MouseEvent.MOUSE_DOWN, arrow_up);
plus.addEventListener(MouseEvent.MOUSE_UP, arrow_stop);
minus.addEventListener(MouseEvent.MOUSE_DOWN, arrow_down);
minus.addEventListener(MouseEvent.MOUSE_UP, arrow_stop);

var move_up:Boolean = false;
var move_down:Boolean = false;



function arrow_up(event:MouseEvent):void
{
    trace("button pressed");
    move_up = true;
}


function arrow_stop(event:MouseEvent):void
{

    move_up = false;
    move_down = false;
}

function arrow_down(event:MouseEvent):void
{

    move_down = true;
}

while (move_up==true)
{
    topArrow.y +=  speed;
}

while (move_down==true)
{
    topArrow.y -=  speed;
}

if(move_up)
{
    trace("true");
}

Answer 1

那些while循環很可怕，一旦move_up為true，它將進入該循環並且永不退出？

我會做以下類似的事情來制作影片剪輯的動畫：

var speed:Number = 1;

plus.addEventListener(MouseEvent.MOUSE_DOWN, arrow_up);
plus.addEventListener(MouseEvent.MOUSE_UP, arrow_stop);
minus.addEventListener(MouseEvent.MOUSE_DOWN, arrow_down);
minus.addEventListener(MouseEvent.MOUSE_UP, arrow_stop);

stage.addEventListener(Event.ENTER_FRAME, onEnterFrame);

var move_up:Boolean = false;
var move_down:Boolean = false;

function arrow_up(event:MouseEvent):void
{
    trace("button pressed");
    move_up = true;
}

function arrow_stop(event:MouseEvent):void
{
    move_up = false;
    move_down = false;
}

function arrow_down(event:MouseEvent):void
{
    move_down = true;
}

function onEnterFrame(event:Event):void
{
   if(move_up)
       topArrow.y += speed;
   else if(move_down)
       topArrow.y -=speed;

   if(move_up)
   {
      trace("true");
   }
}

Answer 2

反編譯二進制文件並查看move_up setter函數。