的FileStream openAsync引發Error＃1009

Question

您好我有一個關於的FileStream openAsync讀取文件有問題，我有一個聽衆和fileReadCompleteHandler等待完整

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(); 

     } 

我得到錯誤：「錯誤＃1009：無法訪問屬性或空對象引用的方法「。 我缺少什麼，如何從openAsync讀取對象？

感謝

Answer 1

你永遠不會初始化目標ob，null對象的過程中訪問領域給你＃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();