【AS3代码】通过两者间的距离，检测是否碰撞

package

{

import com.ui.Ball;

import flash.display.Sprite;

import flash.display.StageAlign;

import flash.display.StageScaleMode;

import flash.events.Event;

import flash.events.MouseEvent;

import flash.geom.Rectangle;

public class Main extends Sprite

{

private var ball:Ball;

private var ball2:Ball;

public function Main():void

{

init();

}

private function init():void

{

ball = new Ball(0x00ffff,Math.random() * 50);

ball.x = stage.stageWidth / 2;

ball.y = stage.stageHeight / 2;

ball2 = new Ball(0xffff00,Math.random() * 50);

ball2.startDrag(true);

this.addChild(ball);

this.addChild(ball2);

stage.addEventListener(Event.ENTER_FRAME, onEnterFrame);

}

private function onEnterFrame(event:Event):void

{

var dx:Number = new Number();

var dy:Number = new Number();

dx = ball2.x - ball.x;

dy = ball2.y - ball.y;

//获得两个球圆心之间的距离公式

var dist:Number = Math.sqrt(dx*dx + dy*dy);

if(dist < (ball.width / 2) + (ball2.width / 2))

{

trace("撞上!");

}

}

}

}