import flash.display.MovieClip;

import flash.geom.ColorTransform;

//方法一

var red:Number = Math.random() * 255 - 255;

var blue:Number = Math.random() * 255 - 255;

var green:Number = Math.random() * 255 - 255;

mc.transform.colorTransform = new ColorTransform(1,1,1,1,red,green,blue);

//方法二

var ct:ColorTransform = new ColorTransform();

ct.color = Math.random() * 0xffffff;

mc.transform.colorTransform = ct;