jQuery Ajax请求失败的所有数据与SQL查询字段

Question

我有一个表格，根据以前的数据填写下一个选择字段，它在PHP8的Localhost/Xampp上工作完美，但现在当我试图在我的服务器上得到它时，它只工作"一次";每一类。

我的问题简化了。

1. 我选择category1，并得到两个结果基于下一个选择
2. 只有一个这些结果与返回数据到第三选择和另一个不返回任何与json_encode，只抛出一个错误的工作

更多信息:

{
"request": "2",
"subcategoryid": "11",
"alakategoriaID": "15"
}
[

正确的响应。

{
"ID": "23",
"name": "Puu 25"
},
{
"ID": "24",
"name": "Puu 50"
}

不返回任何东西的请求

{
"request": "2",
"subcategoryid": "10",
"alakategoriaID": "15"
}

包含select字段等的主函数。

´´´<script>
$(function () {
// Country
$('#sel_country').change(function () {
var categoryID = $(this).val();
// Empty state and city dropdown
$('#sel_state').find('option').not(':first').remove();
$('#sel_city').find('option').not(':first').remove();
$('#varichanger').find('option').not(':first').remove();
// AJAX request
$.ajax({
url: 'helper.php',
type: 'post',
data: {
request: 1,
categoryID: categoryID
},
dataType: 'json',
success: function (response) {
var len = response.length;
for (var i = 0; i < len; i++) {
var id = response[i]['id'];
var name = response[i]['name'];
$("#sel_state").append("<option value='" + id + "'>" + name + "</option>");
}
},
error: function(XMLHttpRequest, textStatus, errorThrown) {
alert("some error");
}
});
$.ajax({
url: 'helper.php',
type: 'post',
data: {
request: 3,
categoryID: categoryID
},
dataType: 'json',
success: function (response) {
var len = response.length;
for (var i = 0; i < len; i++) {
var id = response[i]['id'];
var name = response[i]['name'];
$("#varichanger").append("<option value='" + id + "'>" + name + "</option>");
}
},
error: function(XMLHttpRequest, textStatus, errorThrown) {
alert("some error");
}
});
});
// State
$('#sel_state').change(function () {
var subcategoryid = $(this).val();
var alakategoriaID = $('#sel_country').val();
// Empty city dropdown
$('#sel_city').find('option').not(':first').remove();
// AJAX request
$.ajax({

url: 'helper.php',
type: 'post',
data: {
request: 2,
subcategoryid: subcategoryid,
alakategoriaID: alakategoriaID
},
dataType: 'json',
success: function (response) {
console.log(response);
var len = response.length;
for (var i = 0; i < len; i++) {
var id = response[i]['ID'];
var name = response[i]['name'];
$("#sel_city").append("<option value='" + id + "'>" + name + "</option>");
}
},  
error: function(XMLHttpRequest, textStatus, errorThrown) {
alert("some error");
}
});
});
});
</script>´´´

Helper.php

include "pdoconfig.php";
error_reporting(0);
$request = 0;$request = 0;
if(isset($_POST['request'])){
$request = $_POST['request'];
}
// Fetch subcategory list by categoryID
if(trim($request) == 1){
$categoryID = $_POST['categoryID'];
$stmt = $conn->prepare("SELECT * FROM alakategoriat WHERE kategoriaID=:kategoriaID ORDER BY subcategoryname");
$stmt->bindValue(':kategoriaID', (int)$categoryID, PDO::PARAM_INT);
$stmt->execute();
$subcategorysList = $stmt->fetchAll();
$response = array();
foreach($subcategorysList as $subcategory){
$response[] = array(
"id" => $subcategory['id'],
"name" => $subcategory['subcategoryname']
);
}
echo json_encode($response);
exit;
}
// Fetch city list by subcategoryid
if(trim($request) == 2){
$kategoriaID = $_POST['alakategoriaID'];
$alakategoriaID = $_POST['subcategoryid'];

$stmt = $conn->prepare("SELECT * FROM tuotteet 
WHERE kategoriaID=$kategoriaID
AND alakategoriaID=$alakategoriaID
ORDER BY productname");
$stmt->execute();
$productslist = $stmt->fetchAll();
$response = array();
foreach($productslist as $product){
$response[] = array(
"ID" => $product['ID'],
"name" => $product['productname']
);
}
echo json_encode($response);
exit;
}
if(trim($request) == 3){
$categoryID = $_POST['categoryID'];
$stmt = $conn->prepare("SELECT * 
FROM kategoriavarit 
INNER JOIN varit ON kategoriavarit.variID = varit.variID
WHERE kategoriaID=:kategoriaID");
$stmt->bindValue(':kategoriaID', (int)$categoryID, PDO::PARAM_INT);
$stmt->execute();
$varilist = $stmt->fetchAll();
$response = array();
foreach($varilist as $vari){
$response[] = array(
"id" => $vari['variID'],
"name" => $vari['varinimi']
);
}
echo json_encode($response);
exit;
}

Answer 1

你必须先保存您的类别值会话和第二次使用ajax调用。根据你的代码，你总是得到trim($request) == 1因为每次ajax调用都将其视为新的请求。因此，使用session或cookie存储和使用父类别。

Answer 2

通过清除并重新插入我的数据库值并遵循@Foramkumar Patel的回答来解决问题

编辑:取消，问题是在JSON的响应中使用斯堪的纳维亚字母导致许多不同的问题，通过utf_8编码响应解决了这个问题。