FileReader.readAsBinaryString()
The readAsBinaryString
method is used to start reading the contents of the
specified Blob
or File
. When the read operation is
finished, the readyState
becomes
DONE
, and the FileReader.loadend_event
is triggered. At that time, the
result
attribute contains the raw binary data from
the file.
Note that this method was once removed from the File API specification, but
re-introduced for backward compatibility.
Using FileReader.readAsArrayBuffer()
is recommended.
Syntax
instanceOfFileReader.readAsBinaryString(blob);
Parameters
Example
var canvas = document.createElement('canvas');
var height = 200;
var width = 200;
canvas.width = width;
canvas.height = height;
var ctx = canvas.getContext('2d');
ctx.strokeStyle = '#090';
ctx.beginPath();
ctx.arc(width/2, height/2, width/2 - width/10, 0, Math.PI*2);
ctx.stroke();
canvas.toBlob(function (blob) {
var reader = new FileReader();
reader.onload = function () {
console.log(reader.result);
}
reader.readAsBinaryString(blob);
});
Specifications
Specification |
---|
File API # readAsBinaryString |
Browser compatibility
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