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JavaScript DOM Scripting By Example Adding and Removing Names Registering Names

Primadonna Javier
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Primadonna Javier
iOS Development Techdegree Student 4,236 Points
Posted by Primadonna Javier
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Primadonna Javier
iOS Development Techdegree Student 4,236 Points

ul.createElement is not a function error?

Hi Everyone,

Why am I getting this error on the code above?

Uncaught TypeError: ul.createElement is not a function at HTMLFormElement.<anonymous>

Thanks!

var form = document.getElementById('registrar');
var input = form.querySelector('input');

form.addEventListener('submit', function(e){
    e.preventDefault();
    const text = input.value;
    input.value = '';
    const ul = document.getElementById('invitedList');
    const li = ul.createElement('li');
    li.textContent = text;
    ul.appendChild(li);//add item to the list
});

2 Answers

Tim Acker
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PLUS
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Tim Acker
Front End Web Development Techdegree Graduate 31,247 Points
Tim Acker
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Tim Acker
Front End Web Development Techdegree Graduate 31,247 Points

You create an element on the document object first and then append it as a child to the parent node.

const li = document.createElement('li');
li.textContent = text;
ul.appendChild(li);
andren
andren
28,558 Points
andren
andren
28,558 Points

You get the error pretty much for the exact reason the error states you do, createElement is not a function that exists on HTML elements like ul. The createElement function belongs to the document object. Just like the getElementById function does.

So if you change ul to document like this:

var form = document.getElementById('registrar');
var input = form.querySelector('input');

form.addEventListener('submit', function(e){
    e.preventDefault();
    const text = input.value;
    input.value = '';
    const ul = document.getElementById('invitedList');
    const li = document.createElement('li');
    li.textContent = text;
    ul.appendChild(li);//add item to the list
});

Then your code should work fine.