button click function in js

JavaScript
<script>
  $(document).ready(function(){
    $('#MyButton').click(function(){
       CapacityChart();
    });
  });
</script>

<input type="button" value="Capacity Chart" id="MyButton" ><button onclick="myFunction()">Click me</button>
 <button onclick="myFunction()">Click me</button>

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

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

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