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JavaScript Interactive Web Pages with JavaScript Traversing and Manipulating the DOM with JavaScript Traversing Elements

Xinqi Li
Xinqi Li
3,065 Points

'length' does not work when using .children()

I used var listItems = navigation.children(); but when I get the length of listItems, it says 'undefined' is not an object (evaluating 'listItems.length')

app.js
//Select the navigation
var navigation = document.getElementById("navigation");

//Select all listItems from the navigation
var listItems = navigation.children();

//When a navigation link is pressed
var linkListener = function() {
  console.log("Listener is clicked!");
}

var bindEventsToLinks = function(listItem) {
  //Select the anchor
  var anchor = listItem;
  //Bind the linkListener to the anchor element (a) 
  anchor.onclick = linkListener;
}

for(var i = 0; i < listItems.length ; i++) {
    bindEventsToLinks(listItems[i]);
}
index.html
<!DOCTYPE html>
<html>
<head></head>
<body>

<ul id="navigation">
  <li>
    <a href="#home">Home</a>
  </li>
  <li>
    <a href="#about">About</a>
  </li>
  <li>    
    <a href="#contact">Contact</a>
  </li>
</ul>

<p>A few of my favourite things:</p>
<ul>
  <li>
    Rain drops on roses
  </li>
  <li>
    Whiskers on kittens
  </li>
  <li>
    Brown paper packages wrapped up with string
  </li>
</ul>

<script src="app.js"></script>
</body>
</html>

1 Answer

David Bath
David Bath
25,939 Points

children() is a jQuery method. You need to just use the children property.