nished, the ` result ` attribute contains the
contents of the file as a text string. An optional encoding name can be
specified.

##  Events

Listen to these events using [ ` addEventListener() ` ](/en-
US/docs/Web/API/EventTarget/addEventListener "addEventListener\(\)") or by
assigning an event listener to the ` oneventname ` property of this interface.
Remove the event listeners with [ ` removeEventListener() ` ](/en-
US/docs/Web/API/EventTarget/removeEventListener "removeEventListener\(\)") ,
once ` FileReader ` is no longer used, to avoid memory leaks.

[ ` abort ` ](/en-US/docs/Web/API/FileReader/abort_event "abort")

    

Fired when a read has been aborted, for example because the program called [ `
FileReader.abort() ` ](/en-US/docs/Web/API/FileReader/abort) .

[ ` error ` ](/en-US/docs/Web/API/FileReader/error_event "error")

    

Fired when the read failed due to an error.

[ ` load ` ](/en-US/docs/Web/API/FileReader/load_event "load")

    

Fired when a read has completed successfully.

[ ` loadend ` ](/en-US/docs/Web/API/FileReader/loadend_event "loadend")

    

Fired when a read has completed, successfully or not.

[ ` loadstart ` ](/en-US/docs/Web/API/FileReader/loadstart_event "loadstart")

    

Fired when a read has started.

[ ` progress ` ](/en-US/docs/Web/API/FileReader/progress_event "progress")

    

Fired periodically as data is read.

##  Specifications

Specification  
---  
[ File API  
#  APIASynch  ](https://w3c.github.io/FileAPI/#APIASynch)  
  
##  Browser compatibility

BCD tables only load in the browser  with JavaScript enabled. Enable
JavaScript to view data.

##  See also

  * [ Using files from web applications ](/en-US/docs/Web/API/File_API/Using_files_from_web_applications)
  * [ ` File ` ](/en-US/docs/Web/API/File)
  * [ ` Blob ` ](/en-US/docs/Web/API/Blob)
  * [ ` FileReaderSync ` ](/en-US/docs/Web/API/FileReaderSync)

##  Help improve MDN

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This page was last modified on  Dec 21, 2023  by  [ MDN contributors ](/en-
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