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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 1

Keith Corona
Keith Corona
9,553 Points

Referring to numbers and strings in an array

Hello all,

var answers = 0;
var wrong = 0;

var questions = [
  ['What is the lingua franca?', 'english'], 
  ['What is the capital of California?', 'sacramento'], 
  ['How many lives are cats rumored to have?', 'nine']

function print(message) {

for (var i = 0; i < questions.length; i ++) {
  var guess = prompt(questions[i][0]);

    if (guess.toLowerCase() === questions[i][1]) {

      answers += 1;
       } else {

      wrong += 1;

document.write('You answered correctly to ' + answers + ' question(s) and missed ' + wrong + ' question(s).');

My code, above, seems to work fine, but there is one problem. In my questions array, in the third question (index 2), I wanted to use the number 9 in place of the string nine. I remembered that before we had used parseInt, but with already having added toLowerCase, I wasn't sure how I could do this. What is the correct way to allow numbers and strings for our answers to quiz questions?

Abhishek Bhardwaj
Abhishek Bhardwaj
3,316 Points

try " toString() " Function.

For Example:

var ans = 334; var temp = ans.toString().toLowerCase(); alert(temp);

Abhishek Bhardwaj
Abhishek Bhardwaj
3,316 Points

.toLowerCase function only exists on strings. You can call toString() on anything in javascript to get a string representation.

1 Answer

Casey Ydenberg
Casey Ydenberg
15,622 Points

According to w3cshcools, the value returned from prompt is always a string. To ensure you're comparing strings to strings, use

['How many lives are cats rumoured to have?', '9']

Note the 9 is in quotation marks: still a string! You might want to test this across browsers, just to be sure the behaviour of prompt is consistent.

If you want to parseInt, you'll need a way to NOT apply to the other questions which ARE strings. This is more complicated - you'll need another if to determine whether the expected input can be considered as a number or not.