How to send form data without page refresh?

Question

I have sending my data in ajax using submit button without any page refresh. But the page refreshed.

Please check my code and let me know the problem.

Answer 1

use event.preventdefault()

$("#idForm").submit(function(e) { 
e.preventDefault();//use it here to stop default behaviour
   alert("hi"); 
   var url = "ajax.php";
    $.ajax({
           type: "POST",
           url: url,
           data: $("#idForm").serialize(),
           success: function(data) {
               alert(data);
           }
         });

    return false;
});