(1) (0, 0)에서 한 점까지의 거리 - length

[code as3]
package
{
import flash.display.Sprite;
import flash.display.MovieClip;
import flash.events.MouseEvent;
import flash.geom.Point;

public class Length extends Sprite
{
 public function Length()
 {
  super();
  configureListener();
 }

 private var circle:Circle;

 public function configureListener():void
 {
  if(!circle)
  {
   circle = new Circle();
   circle.x = stage.stageWidth / 2;
   circle.y = stage.stageHeight / 2;
   addChild(circle);
  }

  circle.addEventListener(MouseEvent.MOUSE_DOWN, ptMouseDownHaldner);
  circle.addEventListener(MouseEvent.MOUSE_UP, ptMouseUpHandler);
 }

 function ptMouseDownHaldner(event:MouseEvent):void
 {
  circle.startDrag(false, null);
 }

 function ptMouseUpHandler(event:MouseEvent):void
 {
  circle.stopDrag();
  var point1:Point = new Point(circle.x, circle.y);
  length_txt.text = point1.length.toString();
 }
}
}
[/code]