php上传麻烦

Question

我正在进行php上传，我有一个关于如何自动重命名已存在于文件夹中的文件的问题。你能给我一些关于它的道路或提示吗？感谢

这是我的完整代码 - 代码仅用于测试目的

$destination = 'C:/upload_test/';
$max=75200;
if (isset($_POST['upload'])) {
if (isset($_FILES['image']['tmp_name'])) {
$fileTaille= $_FILES['image']['size'];
if ($fileTaille==true) {
if ($fileTaille > $max) {
    echo "Your file is too large, select a file smaller than". " ".$fileTaille;
    exit(include 'form.php');
   }
 }
   else {
    echo "No file selected";
    exit(include 'form.php');
   }
}

$file_type=getimagesize($_FILES['image']['tmp_name']);

 if ($file_type==true) {
   echo "File is an image - " .$file_type["mime"]." ";
 }
  else{
    echo "Could not get file type";
  }
$fileType = exif_imagetype($_FILES['image']['tmp_name']);
$allowed = array(IMAGETYPE_JPEG, IMAGETYPE_PNG, IMAGETYPE_GIF);

 if (!in_array($fileType, $allowed)) {
   echo "File type not accepted, Only JPEG file allowed";
   exit(include 'form.php');
 }

$sanitize_file = preg_replace("/[^A-Z0-9\.\_-]/i", " ", $_FILES["image"]["name"]);

$fileName = $recipient . basename($recipient);
 if (file_exists($fileName)) {
   echo "File already exist";
   exit(include 'form.php');
 }

}

if (isset($_FILES['image']['tmp_name'])) {
$result = move_uploaded_file($_FILES['image']['tmp_name'], $recipient . $sanitize_file); 

  if ($result == true) {
  echo "file moved "." ";
  }else
    {
    echo "Could not move filed";
    }

  $permission = chmod($$recipient . $sanitize_file, 0644);
  if ($permission==false) {
    echo "No permission to the file";
  }
   else
   {
    echo "permission given";
   }
}