Intercept a form submit in JavaScript and prevent normal submission

Question

There seems to be lots of info on how to submit a form using javascript, but I am looking for a solution to capture when a form has been submitted and intercept it in javascript.

HTML

<form>  <input type="text" name="in" value="some data" />  <button type="submit">Go</button> </form> 

When a user presses the submit button, I do not want the form to be submitted, but instead I would like a JavaScript function to be called.

function captureForm() {  // do some stuff with the values in the form  // stop form from being submitted } 

A quick hack would be to add an onclick function to the button but I do not like this solution... there are many ways to submit a form... e.g. pressing return while on an input, which this does not account for.

Ty

Answer 1

<form id="my-form">     <input type="text" name="in" value="some data" />     <button type="submit">Go</button> </form> 

In JS:

function processForm(e) {     if (e.preventDefault) e.preventDefault();      /* do what you want with the form */      // You must return false to prevent the default form behavior     return false; }  var form = document.getElementById('my-form'); if (form.attachEvent) {     form.attachEvent("submit", processForm); } else {     form.addEventListener("submit", processForm); } 

Edit: in my opinion, this approach is better than setting the onSubmit attribute on the form since it maintains separation of mark-up and functionality. But that's just my two cents.

Edit2: Updated my example to include preventDefault()