How to call a JavaScript function from an onsubmit event?

The onsubmit event occurs when you try to submit a form. You can put your form validation against this event type. The following example shows how to use onsubmit. Here, we are calling a validate() function before submitting a form data to the webserver. If validate() function returns true, the form will be submitted, otherwise it will not submit the data.

<script>    <!--       function validation() {          all validation goes here          .........          return either true or false       }    //--> </script>

The HTML

<form method="POST" action="new.cgi" onsubmit="return validate()">    .......    <input type="submit" value="Submit" /> </form>