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JavaScript Create a Reusable Fetch Function

Posted by Joanna Suau
Joanna Suau
3,754 Points

Getting the "img not defined" reference error in the console

Hi, I have followed along and I think I have the exact same code as the teacher, and yet my console logs an error on line 48. The current behavior of the app is as follows:

  • it loads a random image
  • it loads a list of breeds in the selection box
  • the template literal used the text below the image doesn't change and only says affenpinschers
  • the user can't select a breed from the selection box

Here's my code:

const select = document.getElementById('breeds');
const card = document.querySelector('.card'); 
const form = document.querySelector('form');

// ------------------------------------------
//  FETCH FUNCTIONS
// ------------------------------------------

function fetchData(url) {
  return fetch(url)
    .then(res => res.json())
}

fetchData('https://dog.ceo/api/breeds/list')
  .then(data => generateOptions(data.message))


fetchData('https://dog.ceo/api/breeds/image/random') 
  .then(data => generateImage(data.message))

// ------------------------------------------
//  HELPER FUNCTIONS
// ------------------------------------------

function generateOptions(data) {
  const options = data.map(item => `
    <option value='${item}'>${item}</option>
  `).join('');
  select.innerHTML = options;
}


function generateImage(data) {
  const html = `
     <img src='${data}' alt>
     <p>Click to view images of ${select.value}s</p>         
  `;
  card.innerHTML = html;
}

function fetchBreedImage() {
  const breed = select.value;
  const image = card.querySelector('img');
  const p = card.querySelector('p');

  fetchData(`https://dog.ceo/api/breed/${breed}/images/random`)
    .then(data => {
      img.src = data.message;
      img.alt = breed;
      p.textContent = `Click to view more ${breed}s`;
    })
}


// ------------------------------------------
//  EVENT LISTENERS
// ------------------------------------------

select.addEventListener('click', fetchBreedImage);
card.addEventListener('click', fetchBreedImage);

// ------------------------------------------
//  POST DATA
// ------------------------------------------

2 Answers

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

In "fetchBreedImage", a variable named "image" is defined; but references are made to "img", which is not defined.

And to make it easier to replicate your issue in future questions, make a snapshot of your workspace and post the link to it here.

Joanna Suau
Joanna Suau
3,754 Points

Hi Steven,

thank you for your reply and a link to snapshot taking explanation. Will definitely come in handy!

Regarding my original issue, I thought that this query selector targets any img html tag used in the card div just like the one below for the p tag? the console doesnt log any errors for the p tag. Could you help me a bit more please?

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

The issue is the name of the variable that the query selector is assigned to:

  const image = card.querySelector('img');
//      ^^^^^
//      the variable name is "image"

      img.src = data.message;
//    ^^^
//    but "img" is not defined
Joanna Suau
Joanna Suau
3,754 Points
Joanna Suau
Joanna Suau
3,754 Points

Now this is embarrassing :) thank you so much for your help!