jquery - How to send data from HTML form to Google Spreadsheet using JavaScript?

Question

I'm trying to build a webapp that records datas from a form in a Google Spreadsheet. To do this, I have to use JavaScript (JSON or AJAX requests will work as well), but I cannot use Google Apps Script because I need the user to keep using my pages and GAS doesn't allow it.

I'm not so much versed in JSON requests but I tried to make an append one: no surprise, it's not working and no surprise, I don't know why.

I'm not sure the URL I used to make the request and the code are correct, but not knowing very well how to proceed, it's quite difficult to know what's wrong in my code.

That's my form:

    <form name="reqForm" id="reqForm" method="post" action="" accept-charset="UTF-8" enctype="application/json">
            <input type="hidden" name="area" id="area" readonly/>
            <input type="hidden" name="idN" id="idN" readonly/>
            <input type="hidden" name="dataReq" id="dataReq" readonly />
            <label for="nome">* Nome:</label>
            <input type="text" id="nome" name="nome" placeholder="Il tuo nome" />
            <label for="cognome">* Cognome:</label>
            <input type="text"  id="cognome" name="cognome" placeholder="Il tuo cognome" />
            <label for="mat">* Matricola:</label>
            <input type="text" id="mat" name="mat" placeholder="La tua matricola" />
            <label for="mail">* E-mail:</label>
            <input type="text" id="mail" name="mail" placeholder="La tua e-mail" />
            <label for="testo">* Richiesta:</label>
            <textarea id="testo" name="testo" placeholder="Che cosa vuoi chiedere?"></textarea>
            <button type="button" value="Invia" onClick="check()">Invia</button>
        </form>`

The hidden values are set to provide an ID Number and the user's path.

The check() function will check the form and (should) make the request and write in the GSpreadSheet

    function check() {

document.getElementById('errorForm').innerHTML = "";

var a = document.getElementById('area').value;
var idN = document.getElementById('idN').value;
var n = document.getElementById('nome').value;
var c = document.getElementById('cognome').value;
var m = document.getElementById('mat').value;
var em= document.getElementById('mail').value;
var t = document.getElementById('testo').value;

// check the possible errors and set error messages.
    // if msg is not empty, writes the messages in my page.

} else if(msg == "") {
    var xhr = new XMLHttpRequest();
    var key = mySheetKey, sName =  mySheetName, url = "https://sheets.googleapis.com/v4/spreadsheets/"+key+"/values/"+ sName + ":append?valueInputOption=USER_ENTERED";

    xhr.open("POST", url, true);
    xhr.setRequestHeader("Content-type", "application/json");
    xhr.onreadystatechange = function() {
        if(xhr.readyState === 4 && xhr.status === 200) {
            var json = JSON.parse(xhr.responseText);
        }
    // Here I should create the object made of my variables I read 
    // from my form at the beginning of the code and send the request that
    // should append my datas to my Spreadsheet

    xhr.send();
    } 
    }

As I said before, my code look similar to several ones I found online but it's not working and I don't know how to understand what's wrong.

Could you please kindly give me some tips or advice or some example that could help me appending data to a Google Spreadsheet?

Answer 1

A simple spreadsheet contained web app example

$(function() {
        $('#btn1').click(validate);
        $('#txt4').val('');
        $('#txt3').val('');
        $('#txt2').val('');
        $('#txt1').val('')
      });
function validate()
{
    var txt1 = document.getElementById('txt1').value || ' ';
    var txt2 = document.getElementById('txt2').value || ' ';
    var txt3 = document.getElementById('txt3').value || ' ';
    var txt4 = document.getElementById('txt4').value || ' ';
    var a = [txt1,txt2,txt3,txt4];
    if(txt1 && txt2 && txt3 && txt4)
    {
      google.script.run
        .withSuccessHandler(setResponse)
        .getData(a);
        return true;
    }
    else
    {
      alert('All fields must be completed.');
    }
}

The entire example:

The HTML:

<!DOCTYPE html>
<html>
  <head>
    <base target="_top">
  </head>
  <body>
  <div id="data">
    <br />Text 1<input type="text" size="15" id="txt1" />
    <br />Text 2<input type="text" size="15" id="txt2" />
    <br />Text 3<input type="text" size="15" id="txt3" />
    <br />Text 4<input type="text" size="15" id="txt4" />
    <br /><input type="button" value="submit" id="btn1" />
  </div>
  <div id="resp" style="display:none;">
    <h1>Response</h1>
    <p>Your data has been received.</p>
  </div>
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
    <script>
      $(function() {
        $('#btn1').click(validate);
        $('#txt4').val('');
        $('#txt3').val('');
        $('#txt2').val('');
        $('#txt1').val('')
      });

      function setResponse(a)
      {
        if(a)
        {
          $('#data').css('display','none');
          $('#resp').css('display','block');
        }
      }

      function validate()
      {
        var txt1 = document.getElementById('txt1').value || ' ';
        var txt2 = document.getElementById('txt2').value || ' ';
        var txt3 = document.getElementById('txt3').value || ' ';
        var txt4 = document.getElementById('txt4').value || ' ';
        var a = [txt1,txt2,txt3,txt4];
        if(txt1 && txt2 && txt3 && txt4)
        {
          google.script.run
            .withSuccessHandler(setResponse)
            .getData(a);
            return true;
        }
        else
        {
          alert('All fields must be completed.');
        }
      }

      function loadTxt(from,to)
      {
          document.getElementById(to).value = document.getElementById(from).value;
      }

     console.log('My Code');
   </script>
  </body>
</html>

The Apps Script:

function getData(a)
{
  var ts = Utilities.formatDate(new Date(), "GMT-6", "yyyy-MM-dd' 'HH:mm:ss");
  a.push(ts);
  SpreadsheetApp.getActiveSpreadsheet().getSheetByName('Login').appendRow(a);
  return true;
}

function doGet()
{
  var html = HtmlService.createHtmlOutputFromFile('index');
  return html.setXFrameOptionsMode(HtmlService.XFrameOptionsMode.ALLOWALL)

}

My simple spreadsheet:

The good news is that you're probably a lot better at using the Google Chrome debugger now than before you started.