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JavaScript JavaScript and the DOM Getting a Handle on the DOM Select by Tag Name

Bodie Wood
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Bodie Wood
Full Stack JavaScript Techdegree Student 4,027 Points
Posted by Bodie Wood
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Bodie Wood
Full Stack JavaScript Techdegree Student 4,027 Points

Why doesnt `document.getElementsByTagName('ul');` work?

Hello!

I'm wondering why the code below doesn't work?

document.getElementsByTagName('ul');

Is this because 'ul' is singular?

I eventually answered this question correctly, but I need to know why the above statements doesn't work.

app.js 
// Complete the challenge by writing JavaScript below
const colors = ["#C2272D", "#F8931F", "#FFFF01", "#009245", "#0193D9", "#0C04ED", "#612F90"];
let listItems = document.getElementsByTagName('li');

for ( let i = 0; i < colors.length; i++ ) {
  listItems[i].style.color = colors[i];    
}
index.html 
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>JavaScript and the DOM</title>
  </head>
  <body>
    <h1>My List</h1>
    <ul>
      <li>This should be red</li>
      <li>This should be orange</li>
      <li>This should be yellow</li>
      <li>This should be green</li>
      <li>This should be blue</li>
      <li>This should be indigo</li>
      <li>This should be violet</li>
    </ul>
    <script src="app.js"></script>
  </body>
</html>

1 Answer

josephweiss2
josephweiss2
7,409 Points
josephweiss2
josephweiss2
7,409 Points

That's because when you put "document.getElementsByTagName('ul');" you only select the parent element so you cant run thru it with the "for" loop because its just 1 "UL" and your not selecting the LI items. But when you select the "document.getElementsByTagName('li');" you select all LI elements, and then you can run thru it.