The has()
method of the FormData
interface returns a boolean stating whether a FormData
object contains a certain key.
Note: This method is available in Web Workers.
Syntax
formData.has(name);
Parameters
name
- A
USVString
representing the name of the key you want to test for.
Returns
A Boolean
.
Example
The following line creates an empty FormData
object:
var formData = new FormData();
The following snippet shows the results of testing for the existence of username
in the FormData
object, before and after appending a username
value to it with FormData.append
:
formData.has('username'); // Returns false formData.append('username', 'Chris'); formData.has('username'); // Returns true
Specifications
Specification | Status | Comment |
---|---|---|
XMLHttpRequest The definition of 'has()' in that specification. |
Living Standard |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
has | Chrome Full support 50 | Edge Full support 18 | Firefox Full support 39 | IE No support No | Opera Full support Yes | Safari Full support 11 | WebView Android Full support Yes | Chrome Android Full support 50 | Firefox Android Full support Yes | Opera Android Full support Yes | Safari iOS No support No | Samsung Internet Android Full support 5.0 |
Legend
- Full support
- Full support
- No support
- No support