How do I change more than one element?

Question

EDIT: I changed the var to class but I might have some error in here.

Here it goes, I want to have this paragraph in which the user can change the name on the following paragraph. The code I'm using only changes one name but the rest remains the same.

  <script type="text/javascript">
    function changey(){
      var userInput = document.getElementById('userInput').value;
      var list = document.getElementByClassName('kiddo');

      for (let item of list) {
         item.innerHTML = userInput;
      }
    }
</script>

<input id="userInput" type="text" value="Name of kid" />
<input onclick="changey()" type="button" value="Change Name" /><br>

Welcome to the site <b class="kiddo">dude</b> This is how you create a document that changes the name of the <b class="kiddo">dude</b>. If you want to say <b class="kiddo">dude</b> more times, you can!

No error messages, the code only changes one name instead of all three.

Answer 1

Use class="kiddo" instead of id in the html.

You can then use var kiddos = document.getElementsByClassName('kiddo') which will return an array of all the elements of that class name stored in kiddos .

Then you just need to loop through the values and change what you want.

Example of loop below:

for (var i = 0; i < kiddos.length; i++) {
     kiddos[i].innerHTML = userInput;
}

Answer 2

id should be unique on the page. Javascript assumes that there is only one element with any given id. Instead, you should use a class . Then you can use getElementsByClassName() which returns an entire array of elements that you can iterate over and change. See Select ALL getElementsByClassName on a page without specifying [0] etc for an example.

Answer 3

Hello You should not use id, instead use class.

Welcome to the site <b class="kiddo">dude</b> This is how you create a document that changes the name of the <b class="kiddo">dude</b>. If you want to say <b class="kiddo">dude</b> more times, you can!

After That on Js part :

<script type="text/javascript">
    function changey(){
      var userInput = document.getElementById('userInput').value;
      var list = document.getElementByClassName('kiddo');

      for (let item of list) {
         item.innerHTML = userInput;
      }
    }
</script>

Answer 4

尝试： document.querySelectorAll('.kiddo')与<b class="kiddo">dude</b>

Answer 5

you should use class instated of id. if you use id then the id [kiddo] must be unique

Answer 6

In short, document.querySelectorAll('.kiddo') OR document.getElementsByClassName('kiddo') will get you a list of elements to loop through. Take note of querySelectorAll , though - it uses a CSS selector (note the dot) and doesn't technically return an array (you can still loop through it, though).

See the code below for some full working examples (const and arrow functions are similar to var and function, so I'll put up a version using old JavaScript, too):

 const formEl = document.querySelector('.js-name-change-form') const getNameEls = () => document.querySelectorAll('.js-name') const useNameFromForm = (formEl) => { const formData = new FormData(formEl) const nameValue = formData.get('name') const nameEls = getNameEls() // Set the text of each name element // NOTE: use .textContent instead of .innerHTML - it doesn't get parsed, so it's faster and less work nameEls.forEach(el => el.textContent = nameValue) } // Handle form submit formEl.addEventListener('submit', (e) => { useNameFromForm(e.target) e.preventDefault() // Prevent the default HTTP request }) // Run at the start, too useNameFromForm(formEl) 

 .name { font-weight: bold; } 

 <!-- Using a <form> + <button> (submit) here instead --> <form class="js-name-change-form"> <input name="name" value="dude" placeholder="Name of kid" /> <button>Change Name</button> <form> <!-- NOTE: Updated to use js- for js hooks --> <!-- NOTE: Changed kiddo/js-name to spans + name class to remove design details from the HTML --> <p> Welcome to the site, <span class="js-name name"></span>! This is how you create a document that changes the name of the <span class="js-name name"></span>. If you want to say <span class="js-name name"></span> more times, you can! </p> 

 var formEl = document.querySelector('.js-name-change-form'); var getNameEls = function getNameEls() { return document.querySelectorAll('.js-name'); }; var useNameFromForm = function useNameFromForm(formEl) { var formData = new FormData(formEl); var nameValue = formData.get('name'); var nameEls = getNameEls(); // Set the text of each name element // NOTE: use .textContent instead of .innerHTML - it doesn't get parsed, so it's faster and less work nameEls.forEach(function (el) { return el.textContent = nameValue; }); }; // Handle form submit formEl.addEventListener('submit', function (e) { useNameFromForm(e.target); e.preventDefault(); // Prevent the default HTTP request }); // Run at the start, too useNameFromForm(formEl); 

 <button class="js-get-quote-btn">Get Quote</button> <div class="js-selected-quote"><!-- Initially Empty --></div> <!-- Template to clone --> <template class="js-quote-template"> <div class="js-quote-root quote"> <h2 class="js-quote"></h2> <h3 class="js-author"></h3> </div> </template> 

Answer 7

You have done almost everything right except you caught only first tag with class="kiddo".Looking at your question, as you need to update all the values inside tags which have class="kiddo" you need to catch all those tags which have class="kiddo" using document.getElementsByClassName("kiddo") and looping over the list while setting the innerHTML of each loop element to the userInput. See this link for examples: https://www.w3schools.com/jsref/met_document_getelementsbyclassname.asp