onclick this js code example

Example 1: javascript onclick

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

Example 2: javascript onclick

document.getElementById("Save").onclick = function ()
    {
     alert("hello");
     //validation code to see State field is mandatory.  
    }

Example 3: javascript onclick

var myElem = document.getElementByID('ElemID');
myElem.onclick = function() {
	//do stuff
}