This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The additionalData property of the PasswordCredential interface takes one of a FormData instance, a URLSearchParams instance, or null. The data in the objects will be added to the request body and sent to the remote endpoint with the credentials.
Syntax
passwordCredential.additionalData = formData formData = passwordCredential.additionalData passwordCredential.additionalData = urlSearchParams ulrSearchParams = passwordCredential.additionalData
Value
One of a FormData instance, a URLSearchParams instance, or null.
Example
The following example creates a FormData object with an appended CSRF token. It then stores the form object in the additionalData parameter, before sending it to server in a call to fetch.
//The options object was previously created.
navigator.credentials.get(options).then(function(creds) {
if (creds.type == 'password') {
var form = new FormData();
var csrf_token = document.querySelector('csrf_token').value;
form.append('csrf_token', csrf_token);
creds.additionalData = form;
fetch('https://www.example.com', {
method: 'POST',
credentials: creds
});
};
});
Specifications
| Specification | Status | Comment |
|---|---|---|
| Credential Management Level 1 | Editor's Draft | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | 51.0 | ? | ? | ? | ? |
| Feature | Android | Android Webview | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile | Chrome for Android |
|---|---|---|---|---|---|---|---|---|
| Basic support | No support | 51.0 | ? | ? | ? | ? | ? | 51.0 |