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JavaScript DOM Scripting By Example Adding and Removing Names RSVP Checkbox

Greg Schudel
Greg Schudel
4,090 Points
Posted by Greg Schudel
Greg Schudel
4,090 Points

Questions Javascript Function code

I'm surprized it takes line four lines of code to do something behind the scenes with Javascript. How does the function know where I want to place the element in my app? Why do I need to create an element called input, can't it just be a div?

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

const ul = document.getElementById('invitedList'); // creates element ul

form.addEventListener('submit', (e) => {

  // prevents it  
  e.preventDefault();

  // creates it
  const text= input.value;
  input.value = ''; //clears it
  const li = document.createElement('li'); 


  // checkbox
  const label = document.createElement('label'); // creates element and names it label
  label.textContent = 'Confirmed'; // creates words for that label called 'confirmed' how does it know where to place it in the dom?
  const checkbox = document.createElement('input'); // creates an input? why do I need this?
  checkbox.type = 'checkbox'; // changes the element to be a checkbox.

  //converts it
  li.textContent = text;

  //appends checkbox
  label.appendChild(checkbox);

  // appends ul
  li.appendChild(label);
  ul.appendChild(li);


});

1 Answer

Steven Parker
Steven Parker
229,608 Points
Steven Parker
Steven Parker
229,608 Points

The function knows where to place the new element when you perform these statements:

  li.appendChild(label);  // place the label inside the new list item
  ul.appendChild(li);     // place the new list item at the end of the unordered list

And the reason to create a new "input" element is that will be a functioning check box on the page. A "div" element would not look or act like a check box (at least not without a lot of styling and scripting).