Blob is an interface that represents a blob, which is a file-like object of immutable, raw data; they can be read as text or binary data, or converted into a ReadableStream.
It’s the type of the data received on WebSocket.onmessage when WebSocket.binaryType is set to "blob".
A Blob instance has the following methods/properties:
Class/Property
Description
Blob.size
The number of bytes of data contained within the Blob.
Blob.type
A string containing the MIME type, or an empty string if the type could not be determined.
Blob.arrayBuffer()
Returns a Promise that resolves with the contents of the blob as binary data contained in an ArrayBuffer.
Blob.bytes()
Returns a Promise that resolves with a Uint8Array containing the contents of the blob as an array of bytes.
Blob.slice()
Returns a new Blob object which contains data from a subset of the blob on which it’s called.
Blob.stream()
Returns a ReadableStream which upon reading returns the data contained within the Blob.
Blob.text()
Returns a Promise that resolves with a string containing the contents of the blob, interpreted as UTF-8.