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JavaScript

Code working but not understanding the code

So the following code Is working. However im confused in terms of, what is happening.

const form = document.getElementById("registrar"); //We get the element id "registrar
const input = form.querySelector("input"); // its a form and understands that it has to save, whatever is entered into "input"



form.addEventListener("submit", (e) => { //There is a even listener added, that is a method called submit, it is than told that (e) has to do the following function.
                      e.preventDefault();

const text = input.value; //we store the inputted value in text.
const ul = document.getElementById("invitedList"); // we get the element by ID of the invited list
const li = document.createElement("li"); // Why do we create li?
  li.textContent = text; // What is textContent
 ul.appendChild(li);   //why do we appenChild to ul ? what is the purpose of Li                            
});

1 Answer

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,028 Points
const li = document.createElement("li"); // A list item is a child or a list.
  li.textContent = text; // Gets the text content of a given element.
 ul.appendChild(li);   //The append child method is what adds elements to the not, not createElement.   

So, what's happening is you're getting a reference to the list element (an ordered or an unordered list) so JavaScript knows which element to perform actions on. What you're trying to do here is add a task, or item as a list item (which is of course an <li> a list item.

const li is just what you're naming the attempt to create a list item. the createElement method prepares the DOM to recieve new nodes.

li.textContent grabs the content of the list item. There's a similar one called innerHTML but we're only interested in the text and nothing else.

You've already selected your list ul and written the code to create a new list item. But nothing will happen until you instruct the DOM to add a new node or instance of the element you want to create, which is your list item. i.e. const li.

Hope this makes sense. :)