import flash.filesystem.File;
import flash.filesystem.FileMode;
import flash.filesystem.FileStream;

import flash.utils.ByteArray;

public static function writeAppFile(fileName:String, datas:ByteArray):void{
   var file:File = new File(File.applicationDirectory.resolvePath(fileName).nativePath);
   var fs:FileStream = new FileStream();
   fs.open(file,FileMode.WRITE);
   fs.position = 0;
   fs.writeBytes(datas);
   fs.close();
  }
  public static function readAppFile(fileName:String):void{
   var file:File = new File(File.applicationDirectory.resolvePath(fileName).nativePath);
   var fs:FileStream = new FileStream();
   fs.open(file,FileMode.READ);
   fs.position = 0;
   fs.readBytes(data);
   fs.close();
  }

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