Build a Roman Numeral Converter Project - Build a Roman Numeral Converter

JavaScript
1

Tell us what’s happening:

Hi all,
I’ve gotten this to work by explicitly calling the .value method in my if statements but was curious as to why it doesn’t work if I do so by throwing it in a variable?

Any help is greatly appreciated! I just want to make sure I understand what’s happening here. Also if I am going about this the wrong way with the code that works please let me know.

Your code so far

/* file: script.js */
const userInput = document.getElementById('number');
const convertBtn = document.getElementById('convert-btn');
const result = document.getElementById('output');
// Created to keep from multiple .value method calls
const userInputValue = userInput.value;

// input validation
// only works for both when I explicitly use .value on both input references
const inputValidation = (input) => {
  if (input === '') {
    result.innerText = 'Please enter a valid number';
    return console.log(parseInt(input));
  } else if (parseInt(input) <= -1) {
    result.innerText = 'Please enter a number greater than or equal to 0';
  }
};

// Does not trigger else if - if I use userInputValue
convertBtn.addEventListener('click', () => {
  inputValidation(userInputValue);
})

Your browser information:

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Challenge Information:

Build a Roman Numeral Converter Project - Build a Roman Numeral Converter

2

Just changed my 2nd if statement as well. I noticed that I did not follow directions on that LOL

3

when do you think the value of this is determined? can it change?

4

I think I understand. So because I initialized it as a constant and userInput.value is empty to begin with, it will never update with the new input value. Which is why it only hits the first if statement.

5

it’s not related to const, it’s that you are capturing the value when the app first load, not when the user did something with the app

1 Like
6

Ahhh ok I see. Thank you for clearing things up