FORM_OPEN_DATE   =  "2016-11-23 22:45";
 FORM_CLOSE_DATE  =  "2016-11-23 22:46";
 RESPONSE_COUNT   =  "100";
  
  
 /* Initialize the form, setup time based triggers */
 function Initialize() {
   
   deleteTriggers_();
   
   if ((FORM_OPEN_DATE !== "") && 
       ((new Date()).getTime() < parseDate_(FORM_OPEN_DATE).getTime())) { 
     closeForm();
     ScriptApp.newTrigger("openForm")
     .timeBased()
     .at(parseDate_(FORM_OPEN_DATE))
     .create();
   }
   
   if (FORM_CLOSE_DATE !== "") { 
     ScriptApp.newTrigger("closeForm")
     .timeBased()
     .at(parseDate_(FORM_CLOSE_DATE))
     .create(); 
   }
   
   if (RESPONSE_COUNT !== "") { 
     ScriptApp.newTrigger("checkLimit")
     .forForm(FormApp.getActiveForm())
     .onFormSubmit()
     .create();
   }
   
 }
  
 /* Delete all existing Script Triggers */
 function deleteTriggers_() {  
   var triggers = ScriptApp.getProjectTriggers();  
   for (var i in triggers) {
     ScriptApp.deleteTrigger(triggers[i]);
   }
 }
  
 /* Send a mail to the form owner when the form status changes */
 function informUser_(subject) {
   var formURL = FormApp.getActiveForm().getPublishedUrl();
   MailApp.sendEmail(Session.getActiveUser().getEmail(), subject, formURL);  
 }
  
 /* Allow Google Form to Accept Responses */
 function openForm() {
   var form = FormApp.getActiveForm();
   form.setAcceptingResponses(true);
   informUser_("Your Google Form is now accepting responses");
 }
  
 /* Close the Google Form, Stop Accepting Reponses */
 function closeForm() {  
   var form = FormApp.getActiveForm();
   form.setAcceptingResponses(false);
   deleteTriggers_();
   informUser_("Your Google Form is no longer accepting responses");
 }
  
 /* If Total # of Form Responses >= Limit, Close Form */
 function checkLimit() {
   if (FormApp.getActiveForm().getResponses().length >= RESPONSE_COUNT ) {
     closeForm();
   }  
 }
  
 /* Parse the Date for creating Time-Based Triggers */
 function parseDate_(d) {
   return new Date(d.substr(0,4), d.substr(5,2)-1, 
                   d.substr(8,2), d.substr(11,2), d.substr(14,2));
 }