Blob()

The Blob() constructor returns a new Blob object. The content of the blob consists of the concatenation of the values given in the parameter array.

Syntax

var newBlob = new Blob(array, options);

Parameters

array

An Array of ArrayBuffer, ArrayBufferView, Blob, USVString objects, or a mix of any of such objects, that will be put inside the Blob. USVString objects are encoded as UTF-8.

options Optional

An optional object of type BlobPropertyBag which may specify any of the following properties:

type Optional

The MIME type of the data that will be stored into the blob. The default value is the empty string, ("").

endings Optional

How to interpret newline characters (\n) within the contents, if the data is text. The default value, transparent, copies newline characters into the blob without changing them. To convert newlines to the host system's native convention, specify the value native.

Return value

A new Blob object containing the specified data.

Example

var aFileParts = ['<a id="a"><b id="b">hey!</b></a>']; // an array consisting of a single DOMString
var oMyBlob = new Blob(aFileParts, {type : 'text/html'}); // the blob

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
Blob
20
12
13
Before Firefox 16, the second parameter, when set to null or undefined, leads to an error instead of being handled as an empty dictionary.
10
12
8
37
25
14
Before Firefox 16, the second parameter, when set to null or undefined, leads to an error instead of being handled as an empty dictionary.
12
8
1.5

See also

  • The deprecated BlobBuilder interface which this constructor replaces.

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Blob/Blob