Preventing double HTTP POST

Question

I have made a little app for signing up for an event. User input their data and click \"sign me in\".

Now sometimes people are double in the database, the exact sam

Answer 1

Almost no one has js disabled. Think about coding your e-commerce website for the 70 year old woman who double clicks every link and button. All you want to do is add a javascript to prevent her clicking "Order Now" twice. Yes - check this at the server side too "be defensive" - but don't code for that case. But for the sake of a better UI do it on the client side too.

Here are some scripts that I found:

//
// prevent double-click on submit
//
  jQuery('input[type=submit]').click(function(){
    if(jQuery.data(this, 'clicked')){
      return false;
    }
    else{
      jQuery.data(this, 'clicked', true);
      return true;
    }
  });

and

// Find ALL 
 tags on your page
$('form').submit(function(){
    // On submit disable its submit button
    $('input[type=submit]', this).attr('disabled', 'disabled');
});