s synchronous I/O that
could potentially block.

##  Constructor

[ ` FileReaderSync() ` ](/en-US/docs/Web/API/FileReaderSync/FileReaderSync
"FileReaderSync\(\)")

    

Returns a new ` FileReaderSync ` object.

##  Instance properties

This interface does not have any properties.

##  Instance methods

[ ` FileReaderSync.readAsArrayBuffer() ` ](/en-
US/docs/Web/API/FileReaderSync/readAsArrayBuffer
"FileReaderSync.readAsArrayBuffer\(\)")

    

This method converts a specified [ ` Blob ` ](/en-US/docs/Web/API/Blob) or a [
` File ` ](/en-US/docs/Web/API/File) into an [ ` ArrayBuffer ` ](/en-
US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer) representing the
input data as a binary string.

[ ` FileReaderSync.readAsBinaryString() ` ](/en-
US/docs/Web/API/FileReaderSync/readAsBinaryString
"FileReaderSync.readAsBinaryString\(\)") Deprecated

    

This method converts a specified [ ` Blob ` ](/en-US/docs/Web/API/Blob) or a [
` File ` ](/en-US/docs/Web/API/File) into a string representing the input data
as a binary string. This method is deprecated, consider using `
readAsArrayBuffer() ` instead.

[ ` FileReaderSync.readAsText() ` ](/en-
US/docs/Web/API/FileReaderSync/readAsText "FileReaderSync.readAsText\(\)")

    

This method converts a specified [ ` Blob ` ](/en-US/docs/Web/API/Blob) or a [
` File ` ](/en-US/docs/Web/API/File) into a string representing the input data
as a text string. The optional **` encoding ` ** parameter indicates the
encoding to be used (e.g., iso-8859-1 or UTF-8). If not present, the method
will apply a detection algorithm for it.

[ ` FileReaderSync.readAsDataURL() ` ](/en-
US/docs/Web/API/FileReaderSync/readAsDataURL
"FileReaderSync.readAsDataURL\(\)")

    

This method converts a specified [ ` Blob ` ](/en-US/docs/Web/API/Blob) or a [
` File ` ](/en-US/docs/Web/API/File) into a string representing the input data
as a data URL.

##  Specifications

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

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

##  See also

  * [ ` FileReader ` ](/en-US/docs/Web/API/FileReader)
  * [ ` Blob ` ](/en-US/docs/Web/API/Blob)
  * [ ` File ` ](/en-US/docs/Web/API/File)

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