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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 2 Solution

Marvin Benno
Marvin Benno
7,524 Points
Posted by Marvin Benno
Marvin Benno
7,524 Points

What is wrong with my code?

So i'm trying to make this quiz part 2 and I get the error:

javascript.js:26 Uncaught TypeError: Cannot set property 'innerHTML' of null at print (javascript.js:26) at javascript.js:48

Something seems to be wrong with my .innerHTML. I can't understand what the problem is. Thankfull for feedback!

          <!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>Shaba</title>
</head>

<body>
<h1>
This is my Javascript site.
</h1>
<script src="javascript.js" type="text/javascript"></script>
<div id="output">

</div>
</body>
</html>

var arr = [
    ["hur lång är Marvin Benno? ", "190cm"],
    ["Är Putin och McGregor vänner? ", "ja"],
    ["Hur många dagar finns på ett år? ", "365"],
    ["Vart fiskar Marvin gädda? ", "mälaren"],
    ["1?", "2"]
];
var questionsAsked = 0;
var wrong = 0;
var right = 0;
var answer;
var html;
var htmlRight = "<div> <h1> You got these questions right </h1> <ol>";
var htmlWrong = "<div> <h1> You got these questions wrong </h1> <ol>";
var questionsRight = [];
var questionsWrong = [];

function print(message){
    var outputDiv = document.getElementById('output');
    outputDiv.innerHTML = message;
}


for (var i = 0; i < arr.length; i++) {
    answer = prompt(arr[i][0]);
    questionsAsked += 1;

    if (answer.toLowerCase() === arr[i][1]) {
        right += 1;
        questionsRight.push(arr[i][0]);
        htmlRight += "<li>" + questionsRight[i] + "</li>";
    }
    else {
        wrong += 1;
        questionsWrong.push(arr[i][0]);
        htmlWrong += "<li>" + questionsWrong[i] + "</li>";
    }
}
htmlRight += "</ol> </div>";
htmlWrong += "</ol> </div>";
html = "You got " + right + " out of " + questionsAsked + " answered correct.";
print(html);
print (htmlRight);
print (htmlWrong);

1 Answer

Kyle Gunby
Kyle Gunby
23,838 Points

Try putting the script tag right before the closing body tag. It looks like it's trying to find the div, but it can't. If you let the browser render your div and then run the js code, you should be good.

Marvin Benno
Marvin Benno
7,524 Points
Marvin Benno
Marvin Benno
7,524 Points

Well done bro, thanks!