create event for button code example
Example 1: button click function in js
<script>
$(document).ready(function(){
$('#MyButton').click(function(){
CapacityChart();
});
});
</script>
<input type="button" value="Capacity Chart" id="MyButton" >
Example 2: javascript onclick
// The element id (TheElementID) and var name (myElement) can be named anything.
var myElement = document.getElementByID('TheElementID');
myElement.onclick = function() {
// Carry out a function here...
}