FileReaderSync: readAsArrayBuffer() method
The readAsArrayBuffer() method of the FileReaderSync interface allows to read File or Blob objects in a synchronous way into an ArrayBuffer. This interface is only available in workers as it enables synchronous I/O that could potentially block.
 
Syntax
Parameters
 blob  -  
The File or Blob to read into the File or ArrayBuffer.
   
 
Return value
An ArrayBuffer representing the file's data.
 
Exceptions
The following exceptions can be raised by this method:
  - 
NotFoundError DOMException
  -  
Thrown if the resource represented by the DOM File or Blob cannot be found, e.g. because it has been erased.
   - 
SecurityError DOMException
  -  
Thrown if one of the following problematic situation is detected:
  - the resource has been modified by a third party;
  - too many read are performed simultaneously;
  - the file pointed by the resource is unsafe for a use from the Web (like it is a system file).
  
   - 
NotReadableError DOMException
  -  
Thrown if the resource cannot be read due to a permission problem, like a concurrent lock.
   - 
EncodingError DOMException
  -  
Thrown if the resource is a data URL and exceed the limit length defined by each browser.
   
 
Specifications
Browser compatibility
 | 
Desktop | 
Mobile | 
 | 
Chrome | 
Edge | 
Firefox | 
Internet Explorer | 
Opera | 
Safari | 
WebView Android | 
Chrome Android | 
Firefox for Android | 
Opera Android | 
Safari on IOS | 
Samsung Internet | 
readAsArrayBuffer | 
9 | 
12 | 
8 | 
10 | 
≤12.1 | 
6 | 
4.4 | 
18 | 
8 | 
≤12.1 | 
6 | 
1.0 | 
 
See also