Allows for synchronous reading of File or Blob objects. Only available in Workers, as synchronous I/O would otherwise block the main application from executing.
Important: The FileReaderSync object’s read methods (readAsText, readAsDataURL, and readAsArrayBuffer) have the same method signatures as the read methods of the FileReader object but they behave synchronously (as opposed to asynchronously).
- W3C File API Specification
- W3C Working Draft
Microsoft Developer Network: Windows Internet Explorer API reference Article