PaymentResponse.shippingOption

The shippingOption read-only property of the PaymentRequest interface returns the ID attribute of the shipping option selected by the user. This option is only present when the requestShipping option is set to true in the PaymentOptions object passed to the PaymentRequest constructor.

var shippingOption = PaymentRequest.shippingOption;

In the example below, the PaymentRequest.onshippingaoptionchange event is called. It calls updateDetails() to toggle the shipping method between "standard" and "express".

// Initialization of PaymentRequest arguments are excerpted for brevity.
var payment = new PaymentRequest(supportedInstruments, details, options);

request.addEventListener('shippingoptionchange', function(evt) {
  evt.updateWith(new Promise(function(resolve, reject) {
    updateDetails(details, request.shippingOption, resolve, reject);
  }));
});

payment.show().then(function(paymentResponse) {
  // Processing of paymentResponse exerpted for the same of brevity.
}).catch(function(err) {
  console.error("Uh oh, something bad happened", err.message);
});

function updateDetails(details, shippingOption, resolve, reject) {
  var selectedShippingOption;
  var otherShippingOption;
  if (shippingOption === 'standard') {
    selectedShippingOption = details.shippingOptions[0];
    otherShippingOption = details.shippingOptions[1];
    details.total.amount.value = '55.00';
  } else if (shippingOption === 'express') {
    selectedShippingOption = details.shippingOptions[1];
    otherShippingOption = details.shippingOptions[0];
    details.total.amount.value = '67.00';
  } else {
    reject('Unknown shipping option \'' + shippingOption + '\'');
    return;
  }
  selectedShippingOption.selected = true;
  otherShippingOption.selected = false;
  details.displayItems.splice(2, 1, selectedShippingOption);
  resolve(details);
}