document.getElementByClassName Not working

Baby_Bean · July 3, 2017, 10:40am

Hi everyone
Attached is my code where I want background image of a div to be selected by js:

<!DOCTYPE html>

<html lang = "en">
<head>
  <title>to-forum.html</title>
  <meta charset="utf-8" />
  <style>
  .logo 
  {
    width:1200px;
    height:300px;
    margin:auto;
    display: block; 
    background-repeat:no-repeat;
    position:relative;
    border-radius: 25px;
  }
  </style>
    <script>
      function ChangeImage(param)
      { 
        switch(param)
        {
          case '1':
            return("images/greensilver.gif");
            break;
          case'2':				
            return("images/greensilver1.gif");
            break;
        }
      }
    </script>
</head>

<body>
  <div id="logo"> 
    <script>
      document.getElementByClassName("logo").style.backgroundImage = "url('" + ChangeImage('1') + "')";
    </script>
  </div>
</body>
</html>

The image dont show ! Can you help me the code?

JimL · July 3, 2017, 5:57pm

Check your browsers dev console, it should log an error in your code. You also try to select elements by class, but the div element does not have the class logo.

Hallo_Srood · September 3, 2017, 7:45pm

in the html tag, id=“something” , in the js, it must by get element by id, not by class.