FormData: has() method
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Note: This feature is available in Web Workers.
The has()
method of the FormData
interface returns whether a FormData
object contains a certain key.
Syntax
js
has(name)
Parameters
name
-
A string representing the name of the key you want to test for.
Return value
true
if a key of FormData
matches the specified name
. Otherwise, false
.
Examples
The following snippet shows the results of testing for the existence of username
in a FormData
object, before and after appending a username
value to it with append()
:
js
formData.has("username"); // Returns false
formData.append("username", "Chris");
formData.has("username"); // Returns true
Specifications
Specification |
---|
XMLHttpRequest # dom-formdata-has |
Browser compatibility
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
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has |
Legend
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- Full support
- Full support
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.