javascript addlistener code example

Example 1: javascript onclick event listener

document.getElementById("myBtn").addEventListener("click", function() {
  alert("Hello World!");
});

Example 2: js addeventlistener

document.getElementById("example").addEventListener('click', function() {
  alert('Click');
});

Example 3: javascript addeventlistener

var element = document.getElementById("#id");
element.addEventListener('click', function(){
	console.log("click");
});

Example 4: javascript pass parameter to event listener

var someEventHander=function(){
	console.log(event,param1,param2);
}
//add listener
document.getElementById("someid").addEventListener('click',someEventHander.bind(event,param1,param2));

Example 5: addEventListener

<body style="height: 5000px">
 <style>
    body, /* blink currently has bug that requires declaration on `body` */
    html {
      scroll-snap-type: y proximity;
    }
    .snaptarget {
      scroll-snap-align: start;
      position: relative;
      top: 200px;
      height: 200px;
      background-color: green;
    }
 </style>
 <div class="snaptarget"></div>
</body>

Example 6: addEventListener

<body style="height: 5000px">
 <script>
    function snap(destination) {
        if (Math.abs(destination - window.scrollY) < 3) {
            scrollTo(window.scrollX, destination);
        } else if (Math.abs(destination - window.scrollY) < 200) {
            scrollTo(window.scrollX, window.scrollY + ((destination - window.scrollY) / 2));
            setTimeout(snap, 20, destination);
        }
    }
    var timeoutId = null;
    addEventListener("scroll", function() {
        if (timeoutId) clearTimeout(timeoutId);
        timeoutId = setTimeout(snap, 200, parseInt(document.getElementById('snaptarget').style.top));
    }, true);
 </script>
 <div id="snaptarget" class="snaptarget" style="position: relative; top: 200px; width: 100%; height: 200px; background-color: green"></div>
</body>