Execute javascript code straight before page submit

Question

There are a few similar questions to this but none quite the same.

I want to know if there is an event that can be used to execute some JS before a page is submittin

Answer 1

Something like this?

function do_something(){
   // Do your stuff here
}

If you put return like the code below, you can prevent the form submission by returning false from the do_something() function.

function do_something(){
   // Do your stuff here
   return true; // submit the form

   return false; // don't submit the form
}