$('#add_form').submit(function (e) { //e.preventDefault(); $.ajax({ async: false, type: 'POST', url: '/?eID=r_productsmanager', data: { 'serial_number': $('input[name="tx_rproductsmanager_pi1[serial_number]"]').val(), }, dataType: 'json', success: function(result) { if (result.snResult != true) { e.preventDefault(); alert(result.snResult); } } }); });