how to prevent a form from submitting using javascript code example

Example 1: js stop form submit

<button type="submit" onclick="submitButtonClick(event)">Submit</button>
<script>
function submitButtonClick(event) {
		event.preventDefault();
		//other stuff you want to do instead...
} 
</script>

Example 2: javascript prevent form submit

<form name="foo" onsubmit="return false">