actionscript仿XP矩形鼠标选中框

package
{
	import flash.display.Sprite;
	import flash.events.MouseEvent;
	
	public class mouseDraw extends Sprite
	{
		private var sprite:Sprite;
		private var isDraw:Boolean=false;
		private var x1:Number,x2:Number,y1:Number,y2:Number;
		private var drawNum:int;
		public function mouseDraw()
		{
			initSprite();
						
		}
		function initSprite()
		{
			/*get sprite*/
			sprite=createSprite();
			sprite.addEventListener(MouseEvent.MOUSE_DOWN,startDraw);
			sprite.addEventListener(MouseEvent.MOUSE_MOVE,draw);
			sprite.addEventListener(MouseEvent.MOUSE_UP,stopDraw);
			addChild(sprite);
		}
		
		/*start draw */
		function startDraw(e:MouseEvent):void
		{
			x1=mouseX;
			y1=mouseY;
			this.sprite.graphics.moveTo(x1,y1);
						
			isDraw=true;
			drawNum=1;

		}
		/*move draw*/
		function draw(e:MouseEvent):void
		{
			if(isDraw)
			{
				if(drawNum>1)
				{
					sprite.graphics.clear();
					initSprite();
				}
				x2=mouseX;
				y2=mouseY;
				sprite.graphics.lineStyle(1, 0xFFCC33 );
				this.sprite.graphics.moveTo(x1,y1);
				this.sprite.graphics.lineTo(x2,y1);
				this.sprite.graphics.moveTo(x2,y1);	

				this.sprite.graphics.lineTo(x2,y2);
				this.sprite.graphics.moveTo(x2,y2);

				this.sprite.graphics.lineTo(x1,y2);
				this.sprite.graphics.moveTo(x1,y2);	

				this.sprite.graphics.lineTo(x1,y1);	
				this.sprite.graphics.moveTo(x1,y1);			
				drawNum++;
			}		
		}
		
		/*stop draw*/
		function stopDraw(e:MouseEvent):void
		{
				this.isDraw=false;
				//setChildIndex(this.sprite,numChildren-1);
		}
		
		//create sprite
		function createSprite():Sprite
		{
			var s:Sprite=new Sprite();
			s.graphics.beginFill(0x78D1F5,2);
			s.graphics.drawRoundRect(10,10,300,300,10);
			s.graphics.endFill();
			return s;		
		}

	}
}