jQuery日期选择器从文本文件中读取日期

I’m trying to read dates from a text file for example - '08/12/2017'

$.get('disableDays.txt', function(data) {
     var disableSpecificDays = data;

The values are getting read. I'm then trying to disable dates in the datepicker based on text file entries

It works when I set the value like this:

addDates: ['08/12/2017', '10/14/2017'],

This doesn’t work :

addDates:+ disableSpecificDays,

I’ve tried setting as array but I know jquery is not same as array and like:

addDates:+ $('#disableSpecificDays').val,

var today = new Date();
var y = today.getFullYear();
var dates = $('#full-year').multiDatesPicker({
            //addDates: ['08/12/2017', '10/14/2017'],
//addDates:+ $('#disableSpecificDays').val,
            addDates:+ disableSpecificDays,
                                    numberOfMonths: [3,4],
                                    defaultDate: '1/1/'+y                               
                            beforeShowDay: $.datepicker.noWeekends
                            });

What I am doing wrong?

Can I write back to the text file with:

file_put_contents($file, $current);