FileReaderSync

{{APIRef("File API")}} {{AvailableInWorkers("worker_except_service")}}

The FileReaderSync interface allows to read {{DOMxRef("File")}} or {{DOMxRef("Blob")}} objects synchronously. This interface is only available in workers as it enables synchronous I/O that could potentially block.

Constructor

• {{domxref("FileReaderSync.FileReaderSync", "FileReaderSync()")}}
  • : Returns a new FileReaderSync object.

Instance properties

This interface does not have any properties.

Instance methods

• {{DOMxRef("FileReaderSync.readAsArrayBuffer","FileReaderSync.readAsArrayBuffer()")}}
  • : This method converts a specified {{DOMxRef("Blob")}} or a {{DOMxRef("File")}} into an {{jsxref("ArrayBuffer")}} representing the input data as a binary string.
• {{DOMxRef("FileReaderSync.readAsBinaryString","FileReaderSync.readAsBinaryString()")}} {{deprecated_inline}}
  • : This method converts a specified {{DOMxRef("Blob")}} or a {{DOMxRef("File")}} into a string representing the input data as a binary string. This method is deprecated, consider using readAsArrayBuffer() instead.
• {{DOMxRef("FileReaderSync.readAsText","FileReaderSync.readAsText()")}}
  • : This method converts a specified {{DOMxRef("Blob")}} or a {{DOMxRef("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.
• {{DOMxRef("FileReaderSync.readAsDataURL","FileReaderSync.readAsDataURL()")}}
  • : This method converts a specified {{DOMxRef("Blob")}} or a {{DOMxRef("File")}} into a string representing the input data as a data URL.

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{DOMxRef("FileReader")}}
• {{DOMxRef("Blob")}}
• {{DOMxRef("File")}}