how to click the button in javascript code example

Example 1: javascript click button by id

var button = document.getElementById("button");
button.click();

Example 2: click button javascript

// Create variable for what you are trying to click
let button = document.querySelector("#IDofItem");

// Click the button

if (button) {
  button.click();
}
else {
  console.log("Error");
}

Example 3: button click function in js

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

<input type="button" value="Capacity Chart" id="MyButton" >