as复制效果《三》飘雪

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

public class Snow extends MovieClip {
  var speedx=0;
  var speedy=0;
  public function Snow() {
   speedx=.8 * Math.random() - 0.4;
   speedy=5 * Math.random();
   this.addEventListener(Event.ENTER_FRAME,Mot);
  }
  function Mot(e:Event) {
   this.x+= speedx;
   this.y+= speedy;
   if (this.y >400) {
    init();
   }
  }
  function init() {
   this.y=0;
   this.x=Math.random() * 550;
  }
}
}

flash9中代码：

function DisplaySnows() {
for (var i:int = 0; i < 200; i++) {
  var newSnow:Snow = new Snow();
  this.addChild(newSnow);
  newSnow.x = Math.random()*500;
  newSnow.y =-Math.random()*300;
  newSnow.alpha = .3+Math.random()*.7;

var scale:Number = .3+Math.random();
newSnow.scaleX = newSnow.scaleY = scale;
}
}
DisplaySnows();

补充：flash教程,As3.0