I Keep Getting "Uncaught Syntaxerror: Unexpected Token O"

SyntaxError: Unexpected token o in JSON at position 1

The JSON you posted looks fine, however in your code, it is most likely not a JSON string anymore, but already a JavaScript object. This means, no more parsing is necessary.

You can test this yourself, e.g. in Chrome's console:

new Object().toString()
// "[object Object]"

JSON.parse(new Object())
// Uncaught SyntaxError: Unexpected token o in JSON at position 1

JSON.parse("[object Object]")
// Uncaught SyntaxError: Unexpected token o in JSON at position 1

JSON.parse() converts the input into a string. The toString() method of JavaScript objects by default returns [object Object], resulting in the observed behavior.

Try the following instead:

var newData = userData.data.userList;

how to fix Uncaught SyntaxError: Unexpected token o in JSON at position 1

No need to use parse again , its already json

$.ajax({
                url: "/url/url.ajax?length=100000&startDate=2018-07-01",
                method: "get",
                dataType: "json",
                success: function (jdata) {
                    var jsonData=jdata.data;
                }
            });

$.ajax({

                url: "https://jsonplaceholder.typicode.com/posts",

                method: "get",

                dataType: "json",

                success: function (jdata) {

                    var jsonData=jdata

                    console.log(jsonData)

                }

            });

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

Facing an Uncaught SyntaxError: Unexpected token o in JSON at position 1

first line of showNotes function (line 117 on your screen shot), let Notes = … "Notes" should have a lower "n"

Uncaught SyntaxError: Unexpected token :

I have just solved the problem. There was something causing problems with a standard Request call, so this is the code I used instead:

vote.each(function(element){                
  element.addEvent('submit', function(e){
    e.stop();
    new Request.JSON({
      url : e.target.action, 
      onRequest : function(){
        spinner.show();
      },
      onComplete : function(){
        spinner.hide();
      },
      onSuccess : function(resp){
        var j = resp;
        if (!j) return false;
        var restaurant = element.getParent('.restaurant');
        restaurant.getElements('.votes')[0].set('html', j.votes + " vote(s)");
        $$('#restaurants .restaurant').pop().set('html', "Total Votes: " + j.totalvotes);
        buildRestaurantGraphs();
      }
    }).send(this);
  });
});

If anyone knows why the standard Request object was giving me problems I would love to know.

How to fix Unexpected token o in JSON at position 1 using JavaScript?

add json()
let data = res.json();

Uncaught SyntaxError: Unexpected token o in JSON at position 1 error

You are parsing the data that is already parsed,

try using "data" directly

$("#search").change(function () {
        $("html, body").animate({ scrollTop: $(".calendar").offset().top }, 1500);
        var selectedEvent = $("#search").val();

        $.getJSON('events.json', function (data) {

            render(selectedEvent, data);
        });
    });