how to prevent double click event on submit button

just put this method in your forms then it will handle double click or more clicks in once. once request send it will not allow to send again and again request.

 <script type="text/javascript">
            $(document).ready(function(){
                 $("form").submit(function() {
                        $(this).submit(function() {
                            return false;
                        });
                        return true;
                    }); 
            }); 
            </script>

Use setTimeout for a more user friendly way

$(document).ready(function () {
     $("#btnSubmit").on('click', function (event) {  
           event.preventDefault();
           var el = $(this);
           el.prop('disabled', true);
           setTimeout(function(){el.prop('disabled', false); }, 3000);
     });
});