html script on button click code example

Example 1: javascript button onclick

document.getElementById('button').onclick = function() {
   alert("button was clicked");
};

Example 2: javascript onclick

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

Example 3: javascript onclick button

var button = document.querySelector('button');
button.onclick = function() {
  //do stuff
}