Return the id of the form containing the <keygen> element:
The result of x will be:
The form property returns a reference to the form that contains the keygen field.
This property returns a form object on success.
Note: This property is read only.
The form property is supported in all major browsers, except Internet Explorer.
|Return Value:||A reference to the form element containing the keygen field. If the keygen field is not in a form, null is returned|