无法从服务器中的 php 调用 Ajax 函数

单击提交按钮提交表单后，我从 php 调用 ajax 函数时遇到问题。在本地主机上一切正常，但是当我将所有 php 传输到 FTP 服务器时，所有功能都无法正常工作。

在本地主机中，我可以将文件上传提交到文件系统，我将其命名为"上传"文件夹，然后将表单的数据插入查询数据库。但是当我在FTP服务器上尝试时，我还创建了一个上传文件夹来存储上传的文件，它无法正常工作。

我在代码中做错了什么或需要设置的任何配置？请指出我。

这是我用来提交表单的 php 代码：

学校形式.php

<!--Banner Item No 1 Start-->
<div class="box box-primary1"  id="no1" style="display:block;">
<div class="box-header">
<h3 class="box-title">Upload New Form Here <small>Only PDF</small></h3>
     </div>
     <div class="box-body">
     <form class="form" id="form" action="" method="POST" enctype="multipart/form-data">
     <div class="box-body">
     <div class="form-group" >
     <label for="formName">Form Name</label>
     <input type="text" class="form-control" name="formName" id="formName" placeholder="Please Enter Name" onChange="checkDisabled(testing);">
     </div>
     <div class="form-group" >
     <label for="formDescription">Form Description</label>
     <input type="text" class="form-control" name="formDescription" id="formDescription" placeholder="Please Enter Description" onChange="checkDisabled(testing);">
     </div>
     <div class="form-group">
     <label for="exampleInputFile">File input</label>
     <input type="hidden" name="MAX_FILE_SIZE" value="2000000">
     <input type="file" id="uploaded_file" name="uploaded_file"  onChange="checkDisabled(testing);"><br>
     <p class="help-block">You file must not more than 1MB.     (Only PDF allowed)</p>
     </div> 
     <div class="checkbox">
     <button id="testing" type="submit" class="btn btn-primary" disabled>Add</button>        
     </div>
     </div><!-- /.box-body -->

     </form>         <!-- Date range -->
                     <!-- /.form group -->
                     <!-- Date and time range -->

                     <!-- /.form group -->
                     <!-- Date and time range -->
                     <!-- /.form group -->
                     </div><!-- /.box-body -->
                     </div><!-- /.box -->

这是我用来调用 ajax 函数来插入数据的地方：

//File and text upload with formDATA function
$("#form").submit(function(){
var formData = new FormData($(this)[0]);    
    $.ajax({
        url:'schoolFormItem.php',
        type: 'POST',
        data: formData,
        async: false,
        beforeSend: function(){
        if(confirm('Are you sure?'))
            return true;
        else
            return false;
        },
        cache: false,
        contentType: false,
        processData: false
        }).done(function () {
        //do something if you want when the post is successfully
        if(!alert('Form Had Successfully Inserted.')){document.getelementbyclassname('form').reset()}
                    });
            return false;
  });

这是我将数据插入数据库和文件系统的查询函数：

<?php
include 'dbConnection.php';
global $dbLink;
    $path = "uploads/";
    $valid_formats = array("PDF", "pdf");
    if(isset($_POST) and $_SERVER['REQUEST_METHOD'] == "POST")
        {
            $name = $_FILES['uploaded_file']['name'];
            $size = $_FILES['uploaded_file']['size'];
            $fName = $dbLink->real_escape_string($_POST['formName']);
            $fDescription = $dbLink->real_escape_string($_POST['formDescription']);
            if(strlen($name))
                {
                    list($txt, $ext) = explode(".", $name);
                    if(in_array($ext,$valid_formats))
                    {
                    if($size<(1024*1024))
                        {
                            $actual_image_name = time().substr(str_replace(" ", "_", $txt), 5).".".$ext;
                            $tmp = $_FILES['uploaded_file']['tmp_name'];
                            if(move_uploaded_file($tmp,$path.$actual_image_name))
                                {
                                //mysqli_query ($db,"INSERT INTO image VALUES('','hello','$actual_image_name')");
                                //mysqli_query($db,"UPDATE users SET profile_image='$actual_image_name' WHERE uid='$session_id'");
                                $query = "INSERT INTO schoolform_item (schoolform_name,schoolform_description,schoolform_data,schoolform_created) VALUES ('{$fName}','{$fDescription}','{$actual_image_name}', NOW())";
                                $result = $dbLink->query($query);
                                }
                            else
                                echo "failed";
                        }
                        else
                        echo "Image file size max 1 MB";                        
                        }
                        else
                        echo "Invalid file format..";   
                }
            else
                echo "Please select image..!";
            exit;
        }
?>

我是否错过了任何步骤或有任何代码错误？因为当我使用 xammp 尝试在本地主机上时，一切都在工作。当放在服务器上时，这一切都会出现故障。请指导我完成此操作。