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Request: headers property

The headers read-only property of the Request interface contains the Headers object associated with the request.

Value

A Headers object.

Examples

In the following snippet, we create a new request using the Request() constructor (for an image file in the same directory as the script), then save the request headers in a variable:

js

const myRequest = new Request("flowers.jpg");
const myHeaders = myRequest.headers; // Headers {}

To add a header to the Headers object we use Headers.append; we then create a new Request along with a 2nd init parameter, passing headers in as an init option:

js

const myHeaders = new Headers();
myHeaders.append("Content-Type", "image/jpeg");

const myInit = {
  method: "GET",
  headers: myHeaders,
  mode: "cors",
  cache: "default",
};

const myRequest = new Request("flowers.jpg", myInit);

const myContentType = myRequest.headers.get("Content-Type"); // returns 'image/jpeg'

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
headers 40 14 39 No 27 10.1 40 40 39 27 10.3 4.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/Request/headers