Request: headers property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2017.
Note: This feature is available in Web Workers.
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
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| Fetch # ref-for-dom-request-headers② |
Browser compatibility
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Legend
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