Web/API/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
XMLHttpRequestThe definition of 'keys() (as iterator<>)' in that specification.	Living Standard	Initial definition

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`keys`	Chrome Full support 50	Edge Full support 18	Firefox Full support 44	IE No support No	Opera Full support Yes	Safari Full support 11	WebView Android Full support 50	Chrome Android Full support 50	Firefox Android Full support 44	Opera Android ?	Safari iOS Full support 11	Samsung Internet Android Full support 5.0

Legend

Full support: Full support
No support: No support
Compatibility unknown: Compatibility unknown