how to add an event listener in javascript code example

Example 1: javascript onclick event listener

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

Example 2: event listener javascript

document.getElementById("myBtn").addEventListener("click", displayDate);

Example 3: javascript addeventlistener

//with jQuery
$("#id / .class").on('click', function(){
	console.log("click");
});