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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Getting the First and Last Child

Posted by Maksym Novikov
Maksym Novikov
4,580 Points

How to remove 'up' in the first li and 'down' in last

I wrote this code, but is there any ways to remove 'up' for the each element that standing on the top? The same for the last one

Code:

const listUl = list.querySelector('ul');

function removeMessButtons(ul) { let firstChild = ul.firstElementChild; firstChild.removeChild( firstChild.getElementsByClassName('up')[0] );

let lastChild = ul.lastElementChild; lastChild.removeChild( lastChild.getElementsByClassName('down')[0] ); }

removeMessButtons( listUl );

Maxim Melnic
Maxim Melnic
4,178 Points

ΠœΠ΅ΠΆΠ΄Ρƒ Π½Π°ΠΌΠΈ) Будя ΠΏΠΎ Ρ‚Π²ΠΎΠΈΠΌ ΠΏΠΎΠΈΠ½Ρ‚Π°ΠΌ Ρ‚Ρ‹ Π΄Π°Π»Π΅ΠΊΠΎ ΡƒΡˆΠ΅Π» Π² ΠΈΠ·ΡƒΡ‡Π΅Π½ΠΈΠΈ js Π½Π° этой ΠΏΠ»Π°Ρ‚Ρ„ΠΎΡ€ΠΌΠ΅. Π‘ΠΊΠ°ΠΆΠΈ ΠΌΠ½Π΅, ΠΊΠ°ΠΊ Ρ‚Π΅Π±Π΅ Π² Ρ†Π΅Π»ΠΎΠΌ этот курс?

1 Answer

Maxim Melnic
Maxim Melnic
4,178 Points
Maxim Melnic
Maxim Melnic
4,178 Points

Hi, see my solution:

function hidButtons ()  {
  let ul = document.getElementsByTagName("ul")[0];
  for (let i = 0; i < ul.children.length; i ++) {
  ul.children[i].firstElementChild.style.opacity = "1";
  ul.children[i].lastElementChild.style.opacity = "1";
  }
  ul.firstElementChild.firstElementChild.style.opacity = "0";
  ul.lastElementChild.lastElementChild.style.opacity = "0";
} 
document.addEventListener("click", (event) => {
     hidButtons (); 
 })

hidButtons ();

Note: In my code up button is the first element in <li>, and down button is the last element. Remove button is in center.