PHP上传的文件检索错误

Question

I am building on a simple upload system, below I have the upload system part of the code and the listing. So, I have the directory were all the files uploaded are listed, but when the user clicks on the download button it doesn't work, plus the fact that the code that displays the size shows 0 but the file does get uploaded.

I found out if the files get uploaded on my root directory it is fully functional. And when I change the directory to the root directory the files do get shown and the size and downloading part works ok.

Upload System Code

 if(isset($_FILES['image'])){
  $errors= array();
  $file_name = $_FILES['image']['name'];
  $file_size =$_FILES['image']['size'];
  $file_tmp =$_FILES['image']['tmp_name'];
  $file_type=$_FILES['image']['type'];
  $file_ext=strtolower(end(explode('.',$_FILES['image']['name'])));


  $extensions= array("jpeg","jpg","png", "gif");

  if(in_array($file_ext,$extensions)=== false){
     $errors[]="extension not allowed, please choose a JPEG, PNG, or GIF file.";
  }

  if(empty($errors)==true){
      move_uploaded_file($file_tmp, "dir/.$file_name");
  }else{
     print_r($errors);
  }

}

Retrieving Uploaded Files Code:

     $resource = opendir("dir/.");

        while (($entry = readdir($resource)) != false) {
        $download = '<a href="' . $entry . '"> Download </a> ';

        if ($entry != '.' && $entry != '..') {
            echo "<tr> <td>" . $entry . "</td> <td>" . formatSizeUnits(filesize($entry)) . "</td> <td> $download </td></tr>";   
        }
    }

Answer 1

readdir() doesn't return the full path of the files it finds, literally only their name. Since you opened up dir/ as your source directory, you get somefile.txt , not dir/somefile.txt , which means your filesize is FAILING, because it's looking in the wrong plage. That's not 0 bytes , it's a boolean FALSE being cast to integer 0.