JetFormBuilder JS

code.js

//jQuery submit success
jQuery( document ).on( 'jet-form-builder/ajax/on-success', function( event, response, $form ) {
    //do something
} );

//wp hook on submit
//https://gist.github.com/Crocoblock/d6d1828a785ad55addb8f497deb7f3ba

//to get Observable that represents the form with ID of 128
let observable = JetFormBuilder[128];

//get all form inputs into array
let inputs = observable.getInputs();

//to get field with 'email' name
let email = observable.getInput( 'email' );

//to set 'email' field in this form to some value
email.value.current = '[email protected]'

//clear input
email.onClear();

//to submit the form on some input value change (say, you have a form which contains only one select field, 
//and its change should trigger submit)
let unitType = observable.getInput( 'unit_type' );

unitType.value.watch( function() {
    observable.form.submit()
} );