[jQuery] Ajax form Submit

jquery-form-submit.js

   $(document).ready(function() {
       $.validate();
       // Object as Array
       $.fn.serializeObject = function() {
           var o = {};
           var a = this.serializeArray();
           $.each(a, function() {
               if (o[this.name] !== undefined) {
                   if (!o[this.name].push) {
                       o[this.name] = [o[this.name]];
                   }
                   o[this.name].push(this.value || '');
               } else {
                   o[this.name] = this.value || '';
               }
           });
           return o;
       };
       $("#contactForm").submit(function(event) {
           event.preventDefault();
           var formData = {};
           formData = $('#contactForm').serializeObject();

           $.ajax({
               url: 'http://example.com/endpoint',
               type: "POST",
               data: JSON.stringify(formData),
               contentType: "application/json; charset=utf-8",
               dataType: "json",
               success: function(res) {
                   console.log(res);

               }
           })

       });

   });