flash – 在私人竞争中使用’静态’有什么好处？

静态常量的缺点是所有全局访问都比本地访问慢. instance.ident胜过Class.ident.运行此代码进行测试：

package  {
    import flash.display.Sprite;
    import flash.text.TextField;
    import flash.utils.*;
    public class Benchmark extends Sprite {
        private static const delta:int = 0;
        private const delta:int = 0;        
        private var output:TextField;
        public function Benchmark() {
            setTimeout(doBenchmark,1000);
            this.makeOutput();
        }
        private function doBenchmark():void {
            var i:int,start:int,sum:int,inst:int,cls:int;

            start = getTimer();
            sum = 0;
            for (i = 0; i < 100000000; i++) sum += this.delta;
            out("instance:",inst = getTimer() - start);

            start = getTimer();
            sum = 0;
            for (i = 0; i < 100000000; i++) sum += Benchmark.delta;
            out("class:",cls = getTimer() - start);

            out("instance is",cls/inst,"times faster");
        }   
        private function out(...args):void {
            this.output.appendText(args.join(" ") + "n");
        }
        private function makeOutput():void {
            this.addChild(this.output = new TextField());
            this.output.width = stage.stageWidth;
            this.output.height = stage.stageHeight;
            this.output.multiline = this.output.wordWrap = true;
            this.output.background = true;          
        }       
    }
}