javascript - localstorage value is changed on page refresh -

i creating welcomescreen html app. , im using welcomescreen plugin github. can check here https://github.com/valnub/welcomescreen.js

now want show welcome screen when localstorage value 0. , when close button of welcomescreen clicked changing localstorage value 1. on page refresh localstorage value again set 0.

how js file.

/*jslint browser: true*/  /*global console, welcomescreen, $*/    // init method    $(document).ready(function () {    localstorage.setitem("welscreen", "0");	    var welcometour = localstorage.getitem("welscreen");  	    if (welcometour == 0) {        $(document).ready(function () {              var options = {              'bgcolor': '#0da6ec',              'fontcolor': '#fff',              'onopened': function () {               console.log("welcome screen opened");  	         console.log(welcometour);         },        'onclosed': function () {            localstorage.setitem("welscreen","1");  	      var welcometour = localstorage.getitem("welscreen");  	      console.log("welcome screen closed");  	      console.log(welcometour);          }       },       welcomescreen_slides,       welcomescreen;        welcomescreen_slides = [        {          id: 'slide0',          picture: '<div class="tutorialicon">♥</div>',          text: 'welcome tutorial. in <a class="tutorial-next-          link" href="#">next steps</a> guide through manual teach how use app.'        },        {          id: 'slide1',          picture: '<div class="tutorialicon">✲</div>',          text: 'this slide 2'        },        {          id: 'slide2',          picture: '<div class="tutorialicon">♫</div>',          text: 'this slide 3'        },        {          id: 'slide3',          picture: '<div class="tutorialicon">☆</div>',          text: 'thanks reading! enjoy app or go <a class="tutorial-previous-slide" href="#">previous slide</a>.<br><br><a class="tutorial-close-btn" href="#">end tutorial</a>'        }     ];      welcomescreen = new welcomescreen(welcomescreen_slides, options);      $(document).on('click', '.tutorial-close-btn', function () {      welcomescreen.close();    });      $('.tutorial-open-btn').click(function () {      welcomescreen.open();      });      $(document).on('click', '.tutorial-next-link', function (e) {      welcomescreen.next();     });        $(document).on('click', '.tutorial-previous-slide', function (e) {         welcomescreen.previous();        });           });   };  });

change this:

localstorage.setitem("welscreen", "0");  var welcometour = localstorage.getitem("welscreen"); 

to this:

var welcometour = localstorage.getitem("welscreen"); if(welcometour === undefined || welcometour === null) {    localstorage.setitem("welscreen", "0");    welcometour = "0"; }