public function every_frame(event:Event)
   {
    switch (key_press)
    {
     case 37 :
      tank.x -=  speed;
      tank.rotation = -90;
      break;

     case 38 :
      tank.y -=  speed;
      tank.rotation = 0;
      break;

     case 39 :
      tank.x +=  speed;
      tank.rotation = 90;
      break;

     case 40 :
      tank.y +=  speed;
      tank.rotation = 180;
      break;
    }
   }

package new_proect

{
  import flash.display.*;
  import flash.events.*;
  public class Main extends Sprite
  {
   // make variable to store key state
   var kUp = false;
   var kDown = false;
   var kLeft = false;
   var kRight = false;
   var speed_t = 5;
   var tank = new Hero  ;

   public function Main()
   {
    // constructor code
    tank.x = 225;
    tank.y = 200;
    addChild(tank);
    ////////////////

    stage.addEventListener(KeyboardEvent.KEY_DOWN, kD);
    stage.addEventListener(KeyboardEvent.KEY_UP, kU);
    function kD(k:KeyboardEvent)
    {
     if (k.keyCode == 37)
     {
      kLeft = true;
      kUp = false;
      kDown = false;
      kRight = false;
     }
     if (k.keyCode == 39)
     {
      kRight = true;
      kUp = false;
      kDown = false;
      kLeft = false;
     }
     if (k.keyCode == 38)
     {
      kUp = true;
      kDown = false;
      kLeft = false;
      kRight = false;
     }
     if (k.keyCode == 40)
     {
      kDown = true;
      kUp = false;
      kLeft = false;
      kRight = false;
     }
    }

    function kU(k:KeyboardEvent)
    {
     if (k.keyCode == 37)
     {
      kLeft = false;
     }
     if (k.keyCode == 39)
     {
      kRight = false;
     }
     if (k.keyCode == 38)
     {
      kUp = false;
     }
     if (k.keyCode == 40)
     {
      kDown = false;
     }
    }

    //функция перемещения
    stage.addEventListener(Event.ENTER_FRAME, dvig);
    function dvig(e:Event)
    {
     if (kLeft)
     {
      tank.x -=  speed_t;
      tank.rotation = 270;
     }

     if (kRight)
     {
      tank.x +=  speed_t;
      tank.rotation = 90;
     }

     if (kUp)
     {
      tank.y -=  speed_t;
      tank.rotation = 0;
     }

     if (kDown)
     {
      tank.y +=  speed_t;
      tank.rotation = 180;
     }
    }

   }

  }

}