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Joseph Vincent Trajano
8,014 Pointshelp keep getting this error "Uncaught TypeError: document.getElementsByTagNameName is not a function"
whats wrong with my code?
<!DOCTYPE html> <html> <head> <title>JavaScript and the DOM</title> <link rel="stylesheet" href="css/style.css"> </head> <body> <h1 id="myHeading">JavaScript and the DOM</h1> <p>Making a web page interactive</p> <button id="toggleList">Hide List</button> <div class="list"> <p class="description">Things that are purple:</p> <input type="text" class="description"> <button class="description">Change list description</button> <ul> <li>grapes</li> <li>amethyst</li> <li>lavender</li> <li>plums</li> </ul> <input type="text" class="addItemInput"> <button class="addItemButton">Add Item</button> </div> <script src="app.js"></script> </body> </html>
const toggleList = document.getElementById('toggleList'); const listDiv = document.querySelector('.list'); const descriptionInput = document.querySelector('input.description'); const descriptionP = document.querySelector('p.description'); const descriptionButton = document.querySelector('button.description'); const addItemInput = document.querySelector('input.addItemInput'); const addItemButton = document.querySelector('button.addItemButton');
toggleList.addEventListener('click', () => { if ( listDiv.style.display == 'none' ) { toggleList.textContent = 'Hide list'; listDiv.style.display = 'block'; } else { toggleList.textContent = 'Show list'; listDiv.style.display = 'none'; } });
descriptionButton.addEventListener('click', () => { descriptionP.innerHTML = descriptionInput.value + ':'; });
addItemButton.addEventListener('click', () => { let ul = document.getElementsByTagNameName('ul')[0]; let li = document.createElement(li); li.textContent = addItemInput.value; ul.appendChild('li'); });
1 Answer

Jamie Reardon
Treehouse Project ReviewerYou have written the method as getElementsByTagNameName, it doesn't have Name twice at the end of its name.
getElementsByTagName is the correct syntax.
Joseph Vincent Trajano
8,014 PointsJoseph Vincent Trajano
8,014 Pointshahaha thanks, it was just a simple syntax error.