AJAX/PHP pop up for validation - php

Question

Anyone can help me. Please. I don't how to have a pop up every validation exist.
I used alert(data.message); but validation says undefined.
here is my PHP code for the function:
<?php
include('connect.php');
$mydata = $_POST["results"];
$inputs = [];
parse_str($mydata, $inputs);
extract($inputs);
$plate_no_full = "$plate_char-$plate_no";
$result1 = mysql_query("SELECT * FROM cars where plate_no ='" . $plate_no_full . "'");
$result2 = mysql_query("SELECT * FROM cars where chass_no ='" . $chassis_no . "'");
$result3 = mysql_query("SELECT * FROM cars where eng_no ='" . $engine_no . "'");
$rows1 =mysql_num_rows($result1);
$rows2 =mysql_num_rows($result2);
$rows3 =mysql_num_rows($result3);
$errors = [];
if (mysql_num_rows($result1) > 0) {
$errors[] = array(
'error_code' => 1,
'message' => 'That plate number was already taken'
);
}
if (mysql_num_rows($result2) > 0) {
$errors[] = array(
'error_code' => 2,
'message' => 'That chassis number was already taken'
);
}
if (mysql_num_rows($result3) > 0) {
$errors[] = array(
'error_code' => 3,
'message' => 'That engine number was already taken'
);
}
if(empty($errors)) {
mysql_query("INSERT INTO cars VALUES ('', '$plate_char-$plate_no', '$engine_no', '$chassis_no', '$car_year', '$car_brand', '$car_model', '$horse_power', '$torque','$transmission $transmission_no', '$drivetrain', '$length/$width/$height', '$seating', '$condition','$air_bag' , '$front_wheel/$rear_wheel' , '$front_susp/$rear_susp' , '$brake_front/$brake_rear' , '$eng_type', '$fuel_type' , '$acquisition_cost' , '$marg_cost', '$selling_price' , '')");
if(isset($_POST["txt1"])){
for($i=0;$i<=count($_POST["txt1"])-1;$i++){
mysql_query("INSERT INTO expenses VALUES ('','$plate_char-$plate_no', '". $_POST["txt1"][$i] ."','". $_POST["txt2"][$i] ."', '". $_POST["txt3"][$i] ."')");
}
}
$response = array(
'message' => 'Successfully Added'
);
echo json_encode($response);
} else {
$response = array(
'errors' => $errors
);
echo json_encode($response);
}
here is my ajax code:
$(document).ready(function() {
$('#submitme').on('submit', function(e) {
e.preventDefault();
var mytxt1 = [];
var mytxt2 = [];
var mytxt3 = [];
$(".expense_name").each(function () {
mytxt1.push($(this).val());
});
$(".expense_desc").each(function () {
mytxt2.push($(this).val());
});
$(".expense_cost").each(function () {
mytxt3.push($(this).val());
});
var perfTimes = $(this).serialize();
$.post("addfunction.php", {results: perfTimes, txt1: mytxt1, txt2: mytxt2, txt3: mytxt3 }, function(data) {
if(data.errors) { }
else {
alert(data.message);
window.localtion.href = data.redirect;
}
});
});
});

Answer 1

You need to add the datatype to your post request so jquery can parse the response, then you can handle the errors like you did:
$.post("addfunction.php", {results: perfTimes, txt1: mytxt1, txt2: mytxt2, txt3: mytxt3 }, function (data) {
if (data.errors) {
var alertErrors = "The following errors were found: ";
$.each(data.errors, function(index, error){
alertErrors += "\n" + error.message;//Add each error in a new line
});
alert(alertErrors);
}
else {
alert(data.message);
window.localtion.href = data.redirect;
}
}, "json");//<--datatype here
Also the data.redirect value is missing in your response:
$response = array(
'message' => 'Successfully Added',
'redirect' => ''//add here
);
echo json_encode($response);
Fixing the redirect you wrote "localtion" wrong:
window.location.href = data.redirect;

Answer 2

I found that I needed to parse the returned JSON as well. This is because $.post is just a preconfigured $.ajax call, which does not (I think) specify which dataType is being fetched.
Hence, your Client-side code cannot immediately access the response as an object.
The simplest option is just to parse the response using jQuery:
data = $.parseJSON(data);
Otherwise you could change your code to use the $.ajax function:
$.ajax({
url:url,
type:"POST",
data:data,
contentType:"application/json; charset=utf-8",
dataType:"json",
success: function(){
...
}
})
Good luck!