显示相同的验证消息

Question

我正在制作送餐应用程序。截至目前，我的应用程序无法提交订单。它一直说“订单未添加”尽管页面上有输入且订单没有通过。我相信验证有问题。当我检查控制台时，没有错误。

更新：我已根据要求添加了PHP。

JavaScript的：

$("#btnAddOrder").bind("click", function () {
    AddOrder();
 });

function AddOrder() {

    if ($("#orderform").valid()) {
        var url = serverURL() + "/placeorder.php";
        var JSONObject = {
            "itemID": localStorage.getItem("itemID"),
            "price": localStorage.getItem("price"),
            "quantity": $('#qtytooorder').val(),
            "requestedDateTime": $('#deliverby').val(),
            "userid": localStorage.getItem("userid"),
        };

        $.ajax({
            url: url,
            type: 'GET',
            data: JSONObject,
            dataType: 'json',
            contentType: "application/json; charset=utf-8",
            success: function (arr) {
                _getAddOrderResult(arr);

            },

            error: function () {
                validationMsg();
            }
        });
    }
    else {
        validationMsgs("Please select a date and quantity", "Error", "OK");
    }
}

function _getAddOrderResult(arr) {
    if (arr[0].result === 1) {
        $("#deliverby").val("");
        $("#qtytoorder").val("");
        validationMsgs("Order added.", "Info", "OK");
        window.location = "Orders.html"; //bring him to me.html

    }
    else {
        validationMsgs("Order is not added.", "Error", "OK");
    }
}

HTML：

    <form name="orderform" id="orderform">
        Please deliver by:
        <input type="datetime-local" id="deliverby">
        Quantity to order:
        <input type="text" id="qtytoorder" value="1" />
        <input type="button" value="Order" id="btnAddOrder">
    </form>

PHP：

<?php
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, PATCH, PUT, DELETE, OPTIONS');
header('Access-Control-Allow-Headers: Origin, Content-Type, X-Auth-Token');
header("Content-Type: application/json; charset=UTF-8");

error_reporting(E_ERROR);

include("global.php");

try{
$conn = new mysqli(server, dbuser, dbpw, db);
$userID = $_GET["userID"];
$itemID = $_GET['itemID'];
$price = $_GET['price'];
$quantity = $_GET['quantity'];
$requestedDateTime = $_GET['requestedDateTime'];

$query = "insert into orders (userID, itemID, price, quantity, requestedDateTime, status) values ('$userID','$itemID',$price,$quantity,'$requestedDateTime','ORD')";
$result = $conn->query($query);

if (!$result){
    $json_out = "[" . json_encode(array("result"=>0)) . "]";        
}
else {
    $json_out = "[" . json_encode(array("result"=>1)) . "]";        
}

echo $json_out;

$conn->close();
 }
catch(Exception $e) {
$json_out =  "[".json_encode(array("result"=>0))."]";
echo $json_out;
}
?>