flash as3.0 截图保存图片

import flash.display.MovieClip;
import flash.events.MouseEvent;

import flash.filesystem.*;

//////////////分享////////////////////////////
import flash.display.BitmapData;
import flash.display.Bitmap;
import flash.net.FileReference;
import flash.utils.ByteArray;
import com.JPGEncoder;
shareBtn.addEventListener(MouseEvent.CLICK,clickHD);
function clickHD(evt:MouseEvent):void {
    var bmd:BitmapData=new BitmapData(1920,1080);
    bmd.draw(stage);
    var jpg:JPGEncoder = new JPGEncoder();
    var byteArray:ByteArray = jpg.encode(bmd);
    //var file:FileReference = new FileReference();
    //file.save(byteArray,"1.jpg");

    var file:File=new File();
      file.url = "file:///D:/留言保存目录/" + 22 + ".jpg";
    var stream:FileStream = new FileStream();
    stream.open(file, FileMode.WRITE);
    stream.writeBytes(byteArray);
    stream.close();

}