Web/API/Headers/getAll

Obsolete since Gecko 52 (Firefox 52 / Thunderbird 52 / SeaMonkey 2.49)This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

This is an experimental technologyCheck the Browser compatibility table carefully before using this in production.

The getAll() method of the Headers interface used to return an array of all the values of a header within a Headers object with a given name; in newer versions of the Fetch spec, it has been deleted, and Headers.get() has been updated to fetch all header values instead of only the first one.

If the requested header doesn't exist in the Headers object, it returns an empty array.

For security reasons, some headers can only be controller by the user agent. These headers include the forbidden header names and forbidden response header names.

Syntax

myHeaders.getAll(name);

Parameters

name: The name of the HTTP header whose values you want to retrieve from the Headers object. If the given name is not the name of an HTTP header, this method throws a TypeError.

Returns

An Array containing a ByteString sequence representing the values of the retrieved header.

Example

Creating an empty Headers object is simple:

var myHeaders = new Headers(); // Currently empty

You could add a header to this using Headers.append, then retrieve it using getAll():

myHeaders.append('Content-Type', 'image/jpeg');
myHeaders.getAll('Content-Type'); // Returns [ "image/jpeg" ]

If the header has multiple values associated with it, the array will contain all the values, in the order they were added to the Headers object:

myHeaders.append('Accept-Encoding', 'deflate');
myHeaders.append('Accept-Encoding', 'gzip');
myHeaders.getAll('Accept-Encoding'); // Returns [ "deflate", "gzip" ]

Note: Use Headers.get to return only the first value added to the Headers object.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`getAll` Experimental'Deprecated'Non-standard'	Chrome No support 42 — 60	Edge No support ≤18 — 79	Firefox No support 39 — 52 No support 39 — 52 Full support 34 Disabled' Disabled' From version 34: this feature is behind the `dom.fetch.enabled` preference. To change preferences in Firefox, visit about:config.	IE No support No	Opera No support 29 — 47	Safari No support No	WebView Android No support 42 — 60	Chrome Android No support 42 — 60	Firefox Android No support No	Opera Android No support 29 — 44	Safari iOS No support No	Samsung Internet Android Full support 4.0

Legend

Full support: Full support
No support: No support
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
Non-standard. Expect poor cross-browser support.': Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
User must explicitly enable this feature.': User must explicitly enable this feature.