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

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
Basic supportChrome Full support 50Edge No support NoFirefox Full support 44IE ? Opera Full support YesSafari Full support 11WebView Android ? Chrome Android Full support 50Edge Mobile No support NoFirefox Android Full support 44Opera Android ? Safari iOS ? Samsung Internet Android ?

Legend

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

See also

Document Tags and Contributors

Contributors to this page: ExE-Boss, teoli, jpmedley
Last updated by: ExE-Boss,