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javascripthtmlcssbuttonopacity

How would i get a button to change a objects opacity with html, js & css

I wanted to make a button to hide the weather section of my website landing page but i do not know how to make it! Image

I currently use a "selector" so i can select either 0 or 1 which you can see in the bottom right, and it works nicely but i would perfer a button. Here is my current code that i use:

</div>
  <div class="wopacity">
   <select onchange="myFunction(this);" size="2">
   <option>0
   <option selected="selected">1
   </select>

   <script>
    function myFunction(x) {
     // Return the text of the selected option
     var opacity = x.options[x.selectedIndex].text;
     var el = document.getElementById("p1");
     if (el.style.opacity !== undefined) {
       el.style.opacity = opacity;
     } else {
       alert("Your browser doesn't support this example!");
     }
    }
   </script>
  </div>
Solution

  • If you want to use a button, you could add a data-* attribute to the button. It would look something like

    <html>
<head>
<script>
    function myFunction(button) {
       // get data-opacity
       let opacity = button.dataset.opacity;
       const el = document.getElementById("p1");
       el.style.opacity = opacity;

       /* shorthand for
            if (opacity === "1") {
              button.dataset.opacity === "0";
            else {
              button.dataset.opacity === "1";
            }
       */
       button.dataset.opacity = opacity === "1" ? "0" : "1";
     }
</script>
</head>
<body>
<div id="p1">Opacity test</div>
<button data-opacity="0" onclick="myFunction(this)">Change opacity</button>
</body>
</html>

    Is this actually what you want or did I get the question wrong?