call function on button click code example

Example 1: javascript onclick

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

Example 2: how to call a function with a button in javascript

<script>
		function myFunction()
		{
			document.write("<h1>HELLO</h1>")
		}
	</script>
<button onclick="myFunction()">Click</button>

Example 3: button functions html

<script>
 function myFunction() {
   alert("ALERT");
 }
</script>
<button onclick="myFunction">Click</button>

Example 4: javascript click event

<button onclick="myFunction()">Click me</button>

<p id="demo"></p>

<script>
function myFunction() {
  document.getElementById("demo").innerHTML = "Hello World";
}
</script>

Example 5: javascript onclick

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

Example 6: javascript onclick button

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