var mc:Sprite = new Sprite();

function Control_mc(){
 init();
}

function init():void{
 mc.buttonMode = true;
 mc.graphics.lineStyle(2);
 mc.graphics.beginFill(0xFFCC00);
 mc.graphics.drawCircle(0,0,50);
 mc.x = 200;
 mc.y = 150;
 addChild(mc);
 mc.addEventListener(MouseEvent.MOUSE_DOWN, onMyMouseDown);
 stage.addEventListener(KeyboardEvent.KEY_DOWN, onKeyboardEvent);
}
//滑鼠事件
function onMyMouseDown(event:MouseEvent):void{
 stage.addEventListener(MouseEvent.MOUSE_UP, onMyMouseUp);
 mc.startDrag(false, new Rectangle(50, 50, 300, 200));
}
function onMyMouseUp(event:MouseEvent):void{
 stage.removeEventListener(MouseEvent.MOUSE_UP, onMyMouseUp);
 mc.stopDrag();
}
//鍵盤事件
function onKeyboardEvent(event:KeyboardEvent):void{
 switch(event.keyCode) {
  case 87:if (mc.y > 50){mc.y -= 5}break;
  case 83:if (mc.y < 250){mc.y += 5}break;
  case 65:if (mc.x > 50){mc.x -= 5}break;
  case 68:if (mc.x < 350){mc.x += 5}break;
  default:break;
 }
}

Control_mc();