HTML DOM MouseEvent offsetY Property

HTML Web Development Front End Technology

The HTML DOM MouseEvent offsetY property returns the vertical (y) coordinate of the mouse pointer relative to the target element if a mouse event was triggered. Use with offsetX to get the horizontal coordinate as well.

Following is the syntax −

Returning reference to the offsetY object

MouseEventObject.offsetY

Let us see an example of MouseEvent offsetY property −

Example

Live Demo

<!DOCTYPE html>
<html>
<head>
<title>MouseEvent offsetY</title>
<style>
   * {
      padding: 2px;
      margin:5px;
   }
   form {
      width:70%;
      margin: 0 auto;
      text-align: center;
   }
   #outer {
      width:70%;
      margin: 0 auto;
      padding: 0;
      text-align: center;
      border:1px solid black;
      height: 105px;
      background-color: #28a745;
   }
   input[type="button"] {
      border-radius: 10px;
   }
   #upper {
      border-bottom: 1px solid black;
      height: 40px;
      margin: 0 0 15px 0;
      background-color: #DC3545;
   }
   #lower {
      border-top: 1px solid black;
      height: 40px;
      margin: 15px 0 0 0;
      background-color: #DC3545;
   }
</style>
</head>
<body>
   <form>
      <fieldset>
         <legend>MouseEvent-offsetY</legend>
         <div id="outer">
         <div id="upper"><h2>Danger</h2></div>
         <div id="lower"><h2>Danger</h2></div>
         </div>
         <input type="button" id="start" value="Start" onclick="gameStart()">
         <div id="divDisplay"></div>
      </fieldset>
   </form>
<script>
   var divDisplay = document.getElementById('divDisplay');
   var gameDisplay = document.getElementById('outer');
   function playGame(event) {
      var x = event.offsetX;
      var y = event.offsetY;
         if(y > 45 && y < 60){
            divDisplay.textContent = 'Keep Going!';
               if(x === 272){
                  divDisplay.textContent = 'Congrats! You Did it!';
                  gameDisplay.removeEventListener('mousemove', playGame);
               }
         }
         else{
            divDisplay.textContent = 'You moved to DANGER area. You loose!';
            gameDisplay.removeEventListener('mousemove', playGame);
         }
   }
   function gameStart(){
      gameDisplay.addEventListener('mousemove',playGame);
   }
</script>
</body>
</html>