AS 3.0 stop timer

Question

Hi i need help to stop the timer in a flash game using as 3.0, i need this to pause the game because i move some targets using the getTimer() function, i can make the targets stop their movement when the game is paused but because the getTimer() keeps running when i unpause the game the targets just dissapear from screen (their position changes too fast). is there a way of stopping the timer or a better way of moving my targets as smooth as the getTimer does? her5e is my code:

//animates targets
        private function MoveTarget(e:Event) {

            if (!MovieClip(parent).pauseGame) {
                //get time passed
                timePassed = getTimer() - lastTime;
                lastTime += timePassed;
            }

            //move the target
            this.x += dx * timePassed/1000;

            //check to see if the target is offscreen
            switch (targetType) {
                case "small":
                    if ( dx > 0 && this.x > 771 ) {     //left->right target
                        deleteTarget(false);
                    } else if ( dx < 0 && this.x < -26 ) {  //left<-right target
                        deleteTarget(false);
                    }
                    break;
                case "medium":
                    if ( dx > 0 && this.x > 790 ) {     //left->right target
                        deleteTarget(false);
                    } else if ( dx < 0 && this.x < -40 ) {  //left<-right target
                        deleteTarget(false);
                    }
                    break;
                case "big":
                    if ( dx > 0 && this.x > 800 ) {     //left->right target
                        deleteTarget(false);
                    } else if ( dx < 0 && this.x < -50 ) {  //left<-right target
                        deleteTarget(false);
                    }
                    break;
            }

        }

Answer 1

Here is a simple solution, but I think you should learn what is timestep, it's a critical concept for game programming, see Fix Your Timestep!

if (!MovieClip(parent).pauseGame) {
    //get time passed
    timePassed = getTimer() - lastTime;
    lastTime += timePassed;
}
else
{
    lastTime = getTimer();
    return;
}