Flash Oyun Yaratmak Bölüm 1 - AS3_2

import flash.events.KeyboardEvent;
import flash.events.Event;
import flash.display.MovieClip;

var speed:int = 5;
var key_left:Boolean = false;
var key_right:Boolean = false;
var key_up:Boolean = false;
var key_down:Boolean = false;

stage.addEventListener(KeyboardEvent.KEY_DOWN,KeyDown);
stage.addEventListener(KeyboardEvent.KEY_UP,KeyUp);

addEventListener(Event.ENTER_FRAME,Main);

function Main(event:Event){
    CheckKeys();
}

function KeyDown(event:KeyboardEvent){
    if(event.keyCode == 37){
        key_left = true;
    }
    if(event.keyCode == 39){
        key_right = true;
    }
    if(event.keyCode == 38){
        key_up = true;
    }
    if(event.keyCode == 40){
        key_down = true;
    }
}

function KeyUp(event:KeyboardEvent){
    if(event.keyCode == 37){
        key_left = false;
    }
    if(event.keyCode == 39){
        key_right = false;
    }
    if(event.keyCode == 38){
        key_up = false;
    }
    if(event.keyCode == 40){
        key_down = false;
    }
}

function CheckKeys(){
    if(key_left){
        hero.x -= speed;
    }
    if(key_right){
        hero.x += speed;
    }
    if(key_up){
        hero.y -= speed;
    }
    if(key_down){
        hero.y += speed;
    }
}