Headers.keys()

The Headers.keys() method returns an iterator allowing to go through all keys contained in this object. The keys are String objects.

Note: This method is available in Web Workers.

Syntax

headers.keys();

Return value

Returns an iterator.

Example

// Create a test Headers object
var myHeaders = new Headers();
myHeaders.append('Content-Type', 'text/xml');
myHeaders.append('Vary', 'Accept-Language');

// Display the keys
for(var key of myHeaders.keys()) {
   console.log(key);
}

The result is:

content-type
vary

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
keys
45
16
44
No
32
10.1
45
45
44
32
10.3
5.0

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/Headers/keys