Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.


The readAsArrayBuffer method is used to read the content of the LockedFile object and provide the result of that reading as an ArrayBuffer. In many ways, it performs like the FileReader.readAsArrayBuffer() method.

The reading operation starts at the position given by the LockedFile.location property.


var request = instanceOfLockedFile.readAsArrayBuffer(size);



A number representing the number of bytes to read in the file.


A FileRequest object to handle the success or failure of the operation. In case of success, the request's result is an ArrayBuffer representing the data that have been read.


Specification Status Comment
FileSystem API Editor's Draft Draft proposal

See also