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FormData: keys() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨October 2018⁩.

Note: This feature is available in Web Workers.

The FormData.keys() method returns an iterator which iterates through all keys contained in the FormData. The keys are strings.

Syntax

keys()

Parameters

None.

Return value

An iterator of FormData's keys.

Examples

const formData = new FormData();
formData.append("key1", "value1");
formData.append("key2", "value2");

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

The result is:

key1
key2

Specifications

This feature does not appear to be defined in any specification.>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`keys`	50	18	44	37	11.1	50	44	37	11.3	5.0	50	11.3