How to prefill date in google form - google-apps-script

Question

I'm trying to pre fill the date in google form. so It will put the date of the day it filled as default.
I tried using the TODAY() function in google sheets . so i change the url to get the date from cell in google sheets . works for everything except the Date..
https://docs.google.com/forms/d/e/1FAIpQLSf7cdT34eHp-GXagq3DsnxX1MD_c-G6lbF6yFWOMnUvtPYUUQ/viewform?entry.178275308=**&A6&**
Any idea how can i do it in the simplest way?

Answer 1

Deploy your script as a Web App
Publish your Apps Script as a Web App and provide the URL of the web deployment to the users
Write your code inside a doGet() function, so it gets evaluated every time a user open the link
Get the current date with new Date() and pass it as an itemResponse to a prefilled Form
Create a redirection to the URL to the prefilled form with the Java Script method window.top.location.href inside of <script> </script> tags and return it with HtmlService
// will be automatically run every time the user opens the URL of the web deployment
function doGet(){
//open your form
var form = FormApp.openById('1Zs5Wo0wS9esNkcq8ztOZmQs3f5NrO7hgJ_0fYk262z4');
//get the questions
var questions = form.getItems();
//get the question where you want to prefill the date as an answer, e.g. first question
var question1=questions[0];
//get the current date
var time=Utilities.formatDate(new Date(), "GMT+2", "dd-MM-yyyy");
// prefill form with current date
var prefilledTime=form.createResponse().withItemResponse(question1.asTextItem().createResponse(time));
// Get the link to the prefilled form
var URL=prefilledTime.toPrefilledUrl();
// redirect to the prefilled form URL dynamically created above
return HtmlService.createHtmlOutput("<script>window.top.location.href=\"" + URL + "\";</script>");
}

Answer 2

If you just want the date the Form is submitted, Google Forms provides this automatically in it's Timestamp.
If you want to pre-fill a date from an existing spreadsheet, then provided you obey Google's date-format, you can use the URL approach (months & days must be 2 digits i.e. "01" not "1").
=substitute('Sheet_with_Form_Link'!$A$1,"2099-01-01",text(Sheet_with_date!A1,"yyyy-mm-dd"))
WhereSheet_with_Form_Link'!$A$1 is a cell in a Sheet in a Google SpreadSheet containing the URL obtained via 'Get Prefilled Link'
"2099-01-01" is the data you Pre-filled into the Form whilst using 'Get Pre-filled Link'
Sheet_with_date!A1 is a cell in a Sheet in a Google SpreadSheet containing your desired date e.g. one of
=today()
1920/03/26
17Oct2002

Answer 3

I took the code from ziganotschka as base, but I had to make some changes, maybe it helps somebody:
function doGet(){
//open your form open by URL
var form = FormApp.openByUrl('https://docs.google.com/forms/d/1M-zgHyDOz2ob5StkwIoDCShJ9tePw-I5TGhdx/prefill')
//get the questions
var questions = form.getItems();
//get the question where you want to prefill the date as an answer, e.g. first question
var question1=questions[0];
//get the current date
var time=new Date();
// prefill form with current date
var prefilledTime=form.createResponse().withItemResponse(question1.asDateItem().createResponse(time));
// Get the link to the prefilled form
var URL=prefilledTime.toPrefilledUrl();
// redirect to the prefilled form URL dynamically created above
return HtmlService.createHtmlOutput("<script>window.top.location.href=\"" + URL + "\";</script>");
}
And when you're done, don't forget to Publish -> Deploy as a Web App...