使用PHP错误上传文件

Question

我正在尝试使用以下代码将文件上传到我的服务器：

$feedInstanceID = random_str(32,'0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');

$target_dir = "/home/mysite/public_html/content";



 if(!file_exists($target_dir)) {
   mkdir($target_dir, 0777, true);

 }

 if ($resourceType == "image") {

   $my_file_name = $feedInstanceID . ".jpg";

 }

 else {

   $my_file_name = $feedInstanceID . ".mov"; 

 }

 $target_dir = $target_dir . "/" . basename($_FILES["file"][$my_file_name]);

if (move_uploaded_file($_FILES["file"]["tmp_name"], $target_dir)) 
{
 if ($result) {
  $response["error"] = FALSE;
  echo json_encode($response);
}
else {
  $response["error"] = TRUE;
  $response["error_msg"] = "Can't insert!";
  echo json_encode($response);
}

} else {
 $response["error"] = TRUE;
 $response["error_msg"] = $_FILES["file"]["error"];
 echo json_encode($response);
}

我收到以下错误输出：

[25-Aug-2016 14:18:59 UTC] PHP Notice:  Undefined index: RsmyqMeswmZZ4eo44X14D6bYEgPiobvV.jpg in /home/mysite/public_html/new_upload.php on line 81
[25-Aug-2016 14:18:59 UTC] PHP Warning:  move_uploaded_file(): The second argument to copy() function cannot be a directory in /home/mysite/public_html/new_upload.php on line 83
[25-Aug-2016 14:18:59 UTC] PHP Warning:  move_uploaded_file(): Unable to move '/tmp/phpKMPply' to '/home/mysite/public_html/content/' in /home/mysite/public_html/new_upload.php on line 83