如何从表格中自动更新Google日历中的事件？

Question

我有一个脚本，在提交表单响应时会生成一个事件。但我还希望它通过添加电子邮件作为访客来更新事件，如果事件是同时的话。

我想我需要添加一个If语句然后走这条路，但我不确定谢谢你的帮助

我按照教程来实现这一点，它是：Turn a google form response into a calendar event

我的代码：

//Load the Moment.js library once.
var moment = Moment.load();
var GLOBAL = {
  //the id of the form we will use to create calendar events 
  formId : ("1SfePtYKkseN3Pzdy0wxqVoStKMCJuijW9NT0W9aI1qQ"),
  //the id of the calendar we will create events on
  calendarId : "processing@marketingmobileads.com",

  //a mapping of form item titles to sections of the calendar event
  formMap : {
    eventTitle: "Event Title",
    startTime : "Start",
    endTime: "End",
    email: "Email Address",
  },
}
function onFormSubmit() {
  var eventObject = getFormResponse();
  var event = createCalendarEvent(eventObject);
}
function getFormResponse() {
  // Get a form object by opening the form using the
  // form id stored in the GLOBAL variable object
  var form = FormApp.openById(GLOBAL.formId),
      //Get all responses from the form. 
      //This method returns an array of form responses
      responses = form.getResponses(),
      //find the length of the responses array
      length = responses.length,
      //find the index of the most recent form response
      //since arrays are zero indexed, the last response 
      //is the total number of responses minus one
      lastResponse = responses[length-1],
      //get an array of responses to every question item 
      //within the form for which the respondent provided an answer
      itemResponses = lastResponse.getItemResponses(),
      //create an empty object to store data from the last form response
      //that will be used to create a calendar event
      eventObject = {};
  //Loop through each item response in the item response array
  for (var i = 0, x = itemResponses.length; i<x; i++) {
    //Get the title of the form item being iterated on
    var thisItem = itemResponses[i].getItem().getTitle(),
        //get the submitted response to the form item being
        //iterated on
        thisResponse = itemResponses[i].getResponse();
    //based on the form question title, map the response of the 
    //item being iterated on into our eventObject variable
    //use the GLOBAL variable formMap sub object to match 
    //form question titles to property keys in the event object
    switch (thisItem) {
      case GLOBAL.formMap.eventTitle:
        eventObject.title = thisResponse;
        break;
      case GLOBAL.formMap.startTime:
        eventObject.startTime = thisResponse;
        break;
      case GLOBAL.formMap.endTime:
        eventObject.endTime = thisResponse;
        break; 
      case GLOBAL.formMap.email:
        eventObject.email = thisResponse;
        break;
    }
  }
  return eventObject;
}
function createCalendarEvent(eventObject) {
  //Get a calendar object by opening the calendar using the
  //calendar id stored in the GLOBAL variable object
  var calendar = CalendarApp.getCalendarById(GLOBAL.calendarId),
      //The title for the event that will be created
      title = eventObject.title,
      //The start time and date of the event that will be created
      startTime = moment(eventObject.startTime).toDate(),
      //The end time and date of the event that will be created
      endTime = moment(eventObject.endTime).toDate();
      //an options object containing the description and guest list
      //for the event that will be created
  var options = {
      guests : eventObject.email,
  };
  try {
    //create a calendar event with given title, start time,
    //end time, and description and guests stored in an 
    //options argument
    var event = calendar.createEvent(title, startTime, endTime, options)
  } catch (e) {
    //delete the guest property from the options variable, 
    //as an invalid email address with cause this method to 
    //throw an error.
    delete options.guests
    //create the event without including the guest
    var event = calendar.createEvent(title, startTime, endTime, options)
  }
  return event;   
}