Help with diagonal movement in actionscript 3.0

programming
1

Guys please help! I can only make circ(name of the movieclip in library) move horizontally and vertically using the .x and .y. How do I make it move diagonally?

Here are the codes I used: (I’ve also attached the AS and FLA files)

package
{
import flash.display.MovieClip;
import flash.events.*;

public class ex03 extends MovieClip
{
	public var circ:circleClass;
	public var dir:String = 'right';
	
	public function ex03()
	{
		stop();
		displayCircle();
		stage.addEventListener(Event.ENTER_FRAME,moveCircle);
	}
	public function displayCircle()
	{
		circ = new circleClass();
		circ.x = stage.stageWidth/2;
		circ.y = stage.stageHeight/2;
		circ.width = 100;
		circ.height = 100;
		addChild(circ);
	}
	public function moveCircle (event:Event)
	{
		if(circ.x >= stage.stageWidth - (circ.width/2))
		{
		   dir='left';
		}else if(circ.x<= circ.width/2){
		   dir='right';
	    }
		if(dir=='left')
		{
		   circ.x-=15;
		}else{
		   circ.x+=15;
		}
	}
}

}