Newbie trying to get localStorage to work

Question

I can't get the following code to say anything other than undefined. What am I not doing right? I'm not sure how the score function works, either. So far I've only written vanilla function doSomething() {} methods. Thank you.

var score = score || {};

score = {
  saveHighScore: function(tally) {
    var high_score = localStorage.high_score;
    if (typeof high_score == 'number') {
      if (tally > high_score) {
        localStorage.high_score = tally;
      }
    } else {
      localStorage.high_score = tally;
    }
  },
  getHighScore: function() {
    var high_score = localStorage.high_score;
    if(typeof high_score !== 'number') {
      high_score = 0;
      localStorage.high_score = high_score;
    }
    return high_score;
  }
}

window.console.log("Score: ", score.getHighScore());

I think it does give undefined, as the return value of the `console.log` but before it prints the values, see [this](http://stackoverflow.com/questions/14633968/chrome-firefox-console-log-always-appends-a-line-saying-undefined) — Max Rasguido, Apr 13 '16 at 14:25
I have no idea why, but I reloaded the same code posted above and it returns `Score: 0` in the console. — listenlight, Apr 13 '16 at 14:33

BenG · Accepted Answer · 2016-04-14T08:02:34.037

your problem is local storage stores values as string key/value pairs, so you need to parseInt:-

var score = score || {};

score = {
  saveHighScore: function(tally) {
    var high_score = localStorage.high_score;
    if (typeof high_score == 'number') {
      if (tally > high_score) {
        localStorage.high_score = tally;
      }
    } else {
      localStorage.high_score = tally;
    }
  },
  getHighScore: function() {
    var high_score = parseInt(localStorage.high_score);
    if(typeof high_score !== 'number') {
      high_score = 0;
      localStorage.high_score = high_score;
    }
    return high_score;
  }
}

score.saveHighScore(100)

window.console.log("Score: ", score.getHighScore());

I have no idea why, but I reloaded the same code posted above and it returns Score: 0 in the console.

The reason it is returning 0, is inside getHighScore it retrieves the value from local storage and compares to see if its not a number, then if it isn't you are setting it to 0. as local storage saves all values as a string it is always setting your value to 0.

I'm not sure how the score function works, either

these are just functions inside an object.

Newbie trying to get localStorage to work

1 Answers1