Run JavaScript code on form submission

Question

I want to run a JavaScript code upon a form being submitted preceding other default tasks that are carried out on form submit.

Can anyone suggest some approaches?

Answer 1

For example, here is how you can execute some JS on Drupal's contact form before it is submitted using jQuery:

$('form#contact-mail-page input#edit-submit').click(function() { alert('do some stuff'); });

Answer 2

you can use this property of

'#attributes' => array('onclick' => 'if(confirm('.$msg.')) return true; return false;'));

Answer 3

I am not sure if drupal has any special way to automate this or make it easier but in just normal HTML javascript you would do it like:

<input type="submit" onClick="doStuff();" value="Submit">  //Note: you can use return(doStuff()); and if doStuff returns false then the form will not submit (great for checking if all fields are filled out correctly).