Answers for "how addeventlistener works in javascript"

javascript onclick event listener

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

javascript addeventlistener

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

js addeventlistener

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

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));