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FormData.keys

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

Note: This method is available in Web Workers.

Syntax

formData.keys();

Return value

Returns an iterator.

Example

// Create a test FormData object
var formData = new FormData();
formData.append('key1', 'value1');
formData.append('key2', 'value2');

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

The result is:

key1
key2

Specifications

Specification Status Comment
XMLHttpRequest
The definition of 'keys() (as iterator<>)' in that specification.
Living Standard Initial definition

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 50.0 44 (44) ? (Yes) ?
Available in web workers 50.0 44 (44) ? (Yes) ?
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support 50.0 44.0 (44) ? ? ? 50.0
Available in web workers No support 50.0 44.0 (44) ? ? ? 50.0

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/FormData/keys