Ajax in jquery, php isset cannot detect the value posted - php

Question

I am asking for help with my code. I am trying to get values then send it to php script through ajax by jquery. I can get the values but I don't know what's wrong with it. Your help is appreciated :)
Ajax:
$(".Qty").submit(function(e){
data_form = parseInt($(this).find(".buyQty").val());
id = parseInt($(this).attr('name'));
console.log("id :", id, "Quantity: ", data_form);
$(this).find(".addCart").val('Adding...');
$.ajax({
url: "php/cart_process.php",
type: "POST",
data: {'id': id, 'qty': data_form},
success: function(data){
$("#cart-info").html(data.items);
$(".Qty").find(".addCart").val('Add to Cart');
alert("Item added to Cart!");
if($(".shopping-cart-box").css("display") == "block"){
$(".cart-box").trigger( "click" );
}
},
error: function(XMLHttpRequest, textStatus, errorThrown) {
alert("some error");
}
});
e.preventDefault();
});
php:
<?php
if(isset($_POST['id'])){
$id = $_POST['id'];
echo "<script>console.log('id received: " .$id. "' );</script>";
}
?>

Answer 1

Your php script isn't returning a JSON object like your JS expects.
Your JS expects data to be a JSON object and you are trying to get the value in the index items. E.G data.items
Try this.
PHP
<?php
if(isset($_POST['id'])){
$output = array();
$id = $_POST['id'];
$output['items'] = "<p>id received: {$id} </p>";
echo json_encode($output);
}
?>
JQuery
$(".Qty").submit(function(e){
data_form = parseInt($(this).find(".buyQty").val());
id = parseInt($(this).attr('name'));
console.log("id :", id, "Quantity: ", data_form);
$(this).find(".addCart").val('Adding...');
$.ajax({
url: "php/cart_process.php",
type: "POST",
data: {'id': id, 'qty': data_form},
success: function(data){
console.log('raw data:');
console.log(data);
$("#cart-info").html(data.items);
$(".Qty").find(".addCart").val('Add to Cart');
alert("Item added to Cart!");
if($(".shopping-cart-box").css("display") == "block"){
$(".cart-box").trigger( "click" );
}
},
error: function(XMLHttpRequest, textStatus, errorThrown) {
alert("some error");
}
});
e.preventDefault();
});