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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The get() method of the Headers interface returns the first value of a given header from within a Headers object. If the requested header doesn't exist in the Headers object, the call returns null.

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.get(name);

Parameters

name
The name of the HTTP header whose value 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

A ByteString representing the value of the header retrieved.

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 get():

myHeaders.append('Content-Type', 'image/jpeg');
myHeaders.get('Content-Type'); // Returns 'image/jpeg'

If the header has multiple values associated with it, only the first header value will be returned:

myHeaders.append('Accept-Encoding', 'deflate');
myHeaders.append('Accept-Encoding', 'gzip');
myHeaders.get('Accept-Encoding'); // Returns 'deflate' only, as it was the first value added

Note: Use Headers.getAll to return an array containing all values.

Specifications

Specification Status Comment
Fetch
The definition of 'get()' in that specification.
Living Standard  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 42
41 behind pref
 
39 (39)
34 behind pref
No support

29
28 behind pref

No support
Feature Android Firefox Mobile (Gecko) Firefox OS (Gecko) IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support No support No support No support No support No support No support No support

See also

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