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JavaScript JavaScript and the DOM Making Changes to the DOM Modifying Elements

yueh che yang
yueh che yang
3,707 Points
Posted by yueh che yang
yueh che yang
3,707 Points

Why class selection returns undefined?

Why can't I modify the textContent with this method?

app.js 
var inputValue = document.getElementById('linkText').value;

var p_content = document.getElementsByClass('Info');
p_content.textContent = inputValue;
index.html 
<!DOCTYPE html>
<html>
    <head>
      <title>DOM Manipulation</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
      <div id="content">
        <label for="linkText">Link Text:</label>
        <input type="text" id="linkText" value="sample text">
        <p class="info" id="p"></p>
      </div>
    <script src="app.js"></script>
  </body>
</html>

2 Answers

Alexander Einerskog
Alexander Einerskog
11,932 Points

In your HTML you define the class "info", and in your JavaScript you target the class "Info". Try changing them both to either "Info" or "info". Classes are case sensitive. In addition, the method is called "getElementsByClassName" not "getElementsByClass".