air - FileStream openAsync 抛出错误 #1009

Question

嗨，我有一个关于 FileStream openAsync 读取文件的问题，我有一个监听器并等待完成

    var file:File = File.applicationStorageDirectory.resolvePath(fName+'.'+EXT);
    var fileStream:FileStream = new FileStream();  


     if (!file.exists) {
              this.dispatchEvent(new AppEvent(AppEvent.DATA, null, false));                                         

     }else {

         fileStream.addEventListener(Event.COMPLETE, fileReadCompleteHandler);
         fileStream.openAsync(file, FileMode.READ);
         fileStream.addEventListener(Event.CLOSE, fileClosedHandler);
         fileStream.addEventListener(IOErrorEvent.IO_ERROR, IOErrorHandler);
     }


     private function fileReadCompleteHandler(event:Event):void {
        var ob:Object;
        var fileStream:FileStream = FileStream(event.currentTarget);

        try {
            ob.source = fileStream.readObject();
        }catch (e:Error) {
            trace('error:' + e.message) 
        }

        fileStream.removeEventListener(Event.COMPLETE, fileReadCompleteHandler);
        fileStream.close(); 

      }

在 fileReadCompleteHandler 上，我收到错误:“错误 #1009:无法访问空对象引用的属性或方法。” 我缺少什么，如何从 openAsync 读取对象？

谢谢

Answer 1

你永远不会初始化对象ob，当然访问空对象的字段会给你#1009:

    var ob:Object;
    var fileStream:FileStream = FileStream(event.currentTarget);

    try {
        ob.source = fileStream.readObject();

您需要:

    var ob:Object = new Object;
    var fileStream:FileStream = FileStream(event.currentTarget);

    try {
        ob.source = fileStream.readObject();